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1. accusative
2. Games ace
3. across
4. adenine
5. alto
6. ampere
7. or Å angstrom
8. answer
9. area
10. Sports assist

click for a larger image
Marquee, Radio City Music Hall
Opened in 1932, Radio City Music Hall is a landmark in New York's Rockefeller Center.

a 1

or A  (ā)
n. pl. a's or A's also as or As
1. The first letter of the modern English alphabet.
2. Any of the speech sounds represented by the letter a.
3. The first in a series.
4. Something shaped like the letter A.
5. A The best or highest in quality or rank: grade A milk.
6. Music
a. The sixth tone in the scale of C major or the first tone in the relative minor scale.
b. A key or scale in which A is the tonic.
c. A written or printed note representing this tone.
d. A string, key, or pipe tuned to the pitch of this tone.
7. A One of the four major blood groups in the ABO system. Individuals with this blood group have the A antigen on the surface of their red blood cells, and the anti-B antibody in their blood serum.
from A to Z
Completely; thoroughly.

a 2

 (ə; ā when stressed)
1. Used before nouns and noun phrases that denote a single but unspecified person or thing: a region; a person.
2. Used before terms that denote number, amount, quantity, or degree: only a few of the voters; a bit more rest; a little excited.
a. Used before a proper name to denote a type or a member of a class: the wisdom of a Socrates.
b. Used before a mass noun to indicate a single type or example: a dry wine.
4. The same: birds of a feather.
5. Any: not a drop to drink.

[Middle English, variant of an, an; see an1.]
Usage Note: In writing, the form a is used before a word beginning with a consonant sound, regardless of its spelling (a frog, a university, a euphemism). The form an is used before a word beginning with a vowel sound (an orange, an hour). · An was once a common variant before words beginning with h in which the first syllable was unstressed; thus 18th-century authors wrote either a historical or an historical but a history, not an history. This usage made sense in that people often did not pronounce the initial h in words such as historical and heroic, but by the late 19th century educated speakers usually gave their initial h's a huff, and the practice of writing an before such words began to die out. Nowadays it survives primarily before the word historical. One may also come across it in the phrases an hysterectomy or an hereditary trait. These usages are acceptable in formal writing.

a 3

In every; to each; per: once a month; one dollar a pound.

[Middle English, from Old English an, in; see on.]

a 4

aux.v. Informal
Have: He'd a come if he could.

[Middle English, alteration of haven, to have; see have.]

a 5

1. acceleration
2. are (measurement)


() or


n, pl a's, A's or As
1. (Linguistics) the first letter and first vowel of the modern English alphabet
2. (Phonetics & Phonology) any of several speech sounds represented by this letter, in English as in take, bag, calm, shortage, or cobra
3. (Education) Also called: alpha the first in a series, esp the highest grade or mark, as in an examination
4. from A to Z from start to finish, thoroughly and in detail


(ə; stressed or emphatic)
determiner (indefinite article; used before an initial consonant)
1. used preceding a singular countable noun, if the noun is not previously specified or known: a dog; a terrible disappointment.
2. used preceding a proper noun to indicate that a person or thing has some of the qualities of the one named: a Romeo; a Shylock.
3. used preceding a noun or determiner of quantity: a cupful; a dozen eggs; a great many; to read a lot.
4. used preceding a noun indicating a concrete or abstract thing capable of being divided: half a loaf; a quarter of a minute.
5. (preceded by: once, twice, several times, etc) each or every; per: once a day; fifty pence a pound.
6. a certain; one: to change policy at a stroke; a Mr Jones called.
7. (preceded by not) any at all: not a hope.


an informal or dialect word for have: they'd a said if they'd known.


(usually linked to the preceding noun) an informal form of of: sorta sad; a kinda waste.


symbol for
1. (General Physics) acceleration
2. (Units) are(s) (metric measure of land)
3. (Units) atto-
4. (Chess & Draughts) chess See algebraic notation


symbol for
1. (Classical Music) music
a. a note having a frequency of 440 hertz (A above middle C) or this value multiplied or divided by any power of 2; the sixth note of the scale of C major
b. a key, string, or pipe producing this note
c. the major or minor key having this note as its tonic
2. (Biochemistry) a human blood type of the ABO group, containing the A antigen
3. (Automotive Engineering) (in Britain) a major arterial road: the A3 runs from London to Portsmouth.
4. (Film) (formerly, in Britain)
a. a film certified for viewing by anyone, but which contains material that some parents may not wish their children to see
b. (as modifier): an A film.
5. (General Physics) mass number
6. (Mathematics) the number 10 in hexadecimal notation
7. (Card Games) cards ace
8. (Chemistry) chem argon (now superseded by Ar)
9. (Electronics) ampere(s)
10. (Electrical Engineering) Also: at ampere-turn
11. (General Physics) absolute (temperature)
12. (Electronics) (in circuit diagrams) ammeter
13. (Mathematics) area
14. (General Physics) (in combination) atomic: an A-bomb; an A-plant.
15. (Chemistry) chem affinity
16. (Biochemistry) biochem adenine
17. (Logic) logic a universal affirmative categorical proposition, such as all men are mortal: often symbolized as SaP. Compare E, I2, O1
a. a person whose job is in top management, or who holds a senior administrative or professional position
b. (as modifier): an A worker. See also occupation groupings
abbreviation for
(Automotive Engineering) Austria (international car registration)
[from Latin a(ffirmo) I affirm]


symbol for
(General Physics) angstrom unit

A, a


n., pl. A's As, a's as.
1. the first letter of the English alphabet, a vowel.
2. any spoken sound represented by this letter.
3. something shaped like an A.
4. a written or printed representation of the letter A or a.
from A to Z, from beginning to end; completely; thoroughly: He knows the Bible from A to Z.


(ə; when stressed eɪ)

indefinite article.
1. (used before a singular noun not referring to any specific member of a class or group or referring to a member not previously mentioned): We need a new car. I spoke to a doctor.
2. any; every: A dog has four legs.
3. one: a hundred years; a dozen eggs; a yard of fabric.
4. (used indefinitely with certain quantifiers): a great many years; a few stars.
5. the same: two at a time.
6. a single portion, unit, type, or instance of: two coffees and a tea.
7. a certain; a particular: A Mr. Johnson called.
8. another; one resembling: a Cicero in eloquence.
9. a work by: a Van Gogh.
10. any; a single: not a one.
[Middle English; orig. preconsonantal phonetic variant of an1]
usage: In both spoken and written English a is used before words beginning with a consonant sound (a book), an before words beginning with a vowel sound (an apple). Words that start with vowel letters but are pronounced with the consonant sound (y) or (w) are preceded by a: a union; a European; a one-room apartment. The names of the consonant letters f, h, l, m, n, r, s, and x begin with a vowel sound and thus are preceded by an: an F in geometry; to fly an SST. The names of all other consonants and of the vowel u take a: a B in Spanish; a U-turn. Words that begin with the letter h sometimes cause confusion. When the h is not pronounced, the word is preceded by an: an hour. When h is pronounced, the word is preceded by a: a history of the Sioux; a hero sandwich. (Formerly, an was used before pronounced h:an hundred.) Usage is divided, however, with such words as historian, historical, heroic, and habitual, which begin with an unstressed syllable in which h may be weak or silent. The use of a is widespread in both speech and writing (a historian of ancient China; a habitual criminal), but an is also common. Hotel and unique are occasionally preceded by an, but this use is regarded as old-fashioned.


(ə; when stressed eɪ)

for or in each; for or in every; per: ten cents a ride; three times a day.
[orig. Middle English a, preconsonantal variant of on (see a-1); confused with a1]
usage: See per.



Pron. Spelling. of (often written as part of a single word, without a hyphen): the time a day; kinda; sorta.
[Middle English]



auxiliary verb.
Pron. Spelling. have (often written as part of a single, unhyphenated word): We shoulda gone.
[Middle English]


Physics Symbol.


1. ampere.
2. angstrom.
3. answer.


1. the first in order or in a series.
2. (sometimes l.c.) (in some grading systems) a grade or mark indicating excellence or superiority.
a. the sixth tone of the ascending C major scale.
b. the tonality having A as the tonic.
4. a major blood group. Compare ABO system.
5. adenine.
6. alanine.
7. (formerly) argon.
8. mass number.


are (unit of measurement).


atomic (used in combination): A-bomb; A-plant.


a reduced form of the Old English preposition on, meaning “on,” “in,” “into,” “to,” “toward,” preserved before a noun or adjective in a prepositional phrase, forming a predicate adjective or an adverbial element (afar; afoot; aloud; ashore; away). By analogy with original nominal collocations, a-1 has been joined to verbs, the resulting formation having the force of a present participle (ablaze; astride; awash).
[Middle English, late Old English; compare a2, nowadays]


a reduced form of the Old English preposition of: akin; afresh.


a verbal prefix with the historical sense “out, up,” occurring in verbs and verb derivatives inherited from Old and Middle English, usu. marking the inception or completion of the action denoted by the base verb: abide; accursed; arise; ashamed; awake.
[Middle English; Old English]


var. of ab- before b, m, and v: amanuensis; avert.
[Middle English < Latin ā-, a-]


var. of ad-, used before sc, sp, st (ascend) and in words of French derivation, often with the sense of increase or addition (amass).
[Middle English, in some words < Middle French a- < Latin ad- prefix or ad preposition (see ad-), as in abut; in others < Latin a- (variant of ad- ad-), as in ascend]


var. of an-1 before a consonant: amoral; atonal; achromatic.


a plural ending of nouns borrowed from Greek and Latin: phenomena; criteria; data.


a feminine singular ending of nouns borrowed from Latin and Greek, also used in New Latin coinages to Latinize bases of any origin, and as a Latin substitute for the feminine ending -ē of Greek words: cinchona; pachysandra.


a suffix occurring in the names of oxides of the chemical element denoted by the stem: alumina; thoria.
[probably <-a of magnesia]


1. Absolute.
2. Academy.
3. acre.
4. America.
5. American.
6. year.
[< Latin annō, abl. of annus]
7. before.
[< Latin ante]
8. April.


1. about.
2. acre.
3. active.
4. adjective.
5. alto.
6. ampere.
7. year.
[< Latin annō]
8. anonymous.
9. answer.
10. before.
[< Latin ante]
11. are (unit of measurement).
12. Baseball. assist; assists.


Abbreviation of area


1. 'a' and 'an'

You usually use a and an when it is not clear or important which specific thing or person you are referring to. You only use a and an with singular countable nouns. When you are talking about a specific person or thing, you usually use the.

She decided to buy a car.
He parked the car in front of the bakery.
See the

You can describe someone or something using a or an with an adjective and a noun, or with a noun followed by more information.

His brother was a sensitive child.
The information was contained in an article on biology.

Be Careful!
Don't omit a or an in front of a noun when the noun refers to someone's profession or job. For example, you say 'He is an architect'. Don't say 'He is architect'.

She became a lawyer.
2. 'a' or 'an'?

You use a in front of words beginning with consonant sounds and an in front of words beginning with vowel sounds.

Then I saw a tall woman standing by the window.
We live in an old house.

You use an in front of words beginning with 'h' when the 'h' is not pronounced. For example, you say 'an honest man'. Don't say 'a honest man'.

The meeting lasted an hour.

An is used in front of the following words beginning with 'h':


You use a in front of words beginning with 'u' when the 'u' is pronounced /juː/ (like 'you'). For example, you say 'a unique occasion'. Don't say 'an unique occasion'.

He was a university professor.
She became a union member.

A is used in front of the following words:


You use an in front of an abbreviation when the letters are pronounced separately and the first letter begins with a vowel sound.

Before she became an MP, she was a social worker.
He drives an SUV.
3. 'a' meaning 'one'

A and an are used to mean 'one' in front of some numbers and units of measurement.


Past participle: aed
Gerund: aing

I a
you a
he/she/it as
we a
you a
they a
I aed
you aed
he/she/it aed
we aed
you aed
they aed
Present Continuous
I am aing
you are aing
he/she/it is aing
we are aing
you are aing
they are aing
Present Perfect
I have aed
you have aed
he/she/it has aed
we have aed
you have aed
they have aed
Past Continuous
I was aing
you were aing
he/she/it was aing
we were aing
you were aing
they were aing
Past Perfect
I had aed
you had aed
he/she/it had aed
we had aed
you had aed
they had aed
I will a
you will a
he/she/it will a
we will a
you will a
they will a
Future Perfect
I will have aed
you will have aed
he/she/it will have aed
we will have aed
you will have aed
they will have aed
Future Continuous
I will be aing
you will be aing
he/she/it will be aing
we will be aing
you will be aing
they will be aing
Present Perfect Continuous
I have been aing
you have been aing
he/she/it has been aing
we have been aing
you have been aing
they have been aing
Future Perfect Continuous
I will have been aing
you will have been aing
he/she/it will have been aing
we will have been aing
you will have been aing
they will have been aing
Past Perfect Continuous
I had been aing
you had been aing
he/she/it had been aing
we had been aing
you had been aing
they had been aing
I would a
you would a
he/she/it would a
we would a
you would a
they would a
Past Conditional
I would have aed
you would have aed
he/she/it would have aed
we would have aed
you would have aed
they would have aed


A member of the highest grouping into which society is divided by occupation, typically a senior manager, administrator, or professional.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.A - a metric unit of length equal to one ten billionth of a meter (or 0.0001 micron); used to specify wavelengths of electromagnetic radiation
metric linear unit - a linear unit of distance in metric terms
micromicron, picometer, picometre - a metric unit of length equal to one trillionth of a meter
micromillimeter, micromillimetre, millimicron, nanometer, nanometre, nm - a metric unit of length equal to one billionth of a meter
2.A - any of several fat-soluble vitamins essential for normal visionA - any of several fat-soluble vitamins essential for normal vision; prevents night blindness or inflammation or dryness of the eyes
fat-soluble vitamin - any vitamin that is soluble in fats
retinol, vitamin A1 - an unsaturated alcohol that occurs in marine fish-liver oils and is synthesized biologically from carotene
dehydroretinol, vitamin A2 - a viscous alcohol that is less active in mammals than is vitamin A1
3.A - one of the four nucleotides used in building DNAA - one of the four nucleotides used in building DNA; all four nucleotides have a common phosphate group and a sugar (ribose)
nucleotide, base - a phosphoric ester of a nucleoside; the basic structural unit of nucleic acids (DNA or RNA)
4.A - (biochemistry) purine base found in DNA and RNAA - (biochemistry) purine base found in DNA and RNA; pairs with thymine in DNA and with uracil in RNA
biochemistry - the organic chemistry of compounds and processes occurring in organisms; the effort to understand biology within the context of chemistry
purine - any of several bases that are derivatives of purine
deoxyribonucleic acid, desoxyribonucleic acid, DNA - (biochemistry) a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information; "DNA is the king of molecules"
ribonucleic acid, RNA - (biochemistry) a long linear polymer of nucleotides found in the nucleus but mainly in the cytoplasm of a cell where it is associated with microsomes; it transmits genetic information from DNA to the cytoplasm and controls certain chemical processes in the cell; "ribonucleic acid is the genetic material of some viruses"
5.A - the basic unit of electric current adopted under the Systeme International d'UnitesA - the basic unit of electric current adopted under the Systeme International d'Unites; "a typical household circuit carries 15 to 50 amps"
current unit - a measure of the amount of electric charge flowing past a circuit point at a specific time
milliampere, mA - one thousandth of an ampere
abamp, abampere - a unit of current equal to 10 amperes
6.A - the 1st letter of the Roman alphabeta - the 1st letter of the Roman alphabet
Latin alphabet, Roman alphabet - the alphabet evolved by the ancient Romans which serves for writing most of the languages of western Europe
alphabetic character, letter of the alphabet, letter - the conventional characters of the alphabet used to represent speech; "his grandmother taught him his letters"
7.A - the blood group whose red cells carry the A antigenA - the blood group whose red cells carry the A antigen
blood group, blood type - human blood cells (usually just the red blood cells) that have the same antigens


a1 [eɪ]
A. N
1. (= letter) → A, a f
A for AndrewA de Antonio
to get from A to Bir de A a B
No. 32A (= house) → núm. 32 bis, núm. 32 duplicado
the A-Z of Management Techniquesel manual básico de Técnicas de Gestión, Técnicas de Gestión de la A a la Z
to know sth from A to Zconocer algo de pe a pa or de cabo a rabo
2. (Mus) Ala m
A major/minorla mayor/menor
A sharp/flatla sostenido/bemol
3. (Scol) → sobresaliente m
B. CPD A level N ABBR (Brit) (Scol) =Advanced levelbachillerato m
to take three A levelspresentarse como candidato en tres asignaturas de A level
she has an A level in chemistrytiene un título de A level en química
A road N (Brit) → carretera f nacional
"A" shares NPLacciones fpl de clase A
A side N [of record] → cara f A
A to Z® N (= map book) → callejero m
Al terminar la educación secundaria obligatoria, los estudiantes de Inglaterra, Gales e Irlanda del Norte pueden estudiar otros dos años para preparar dos o tres asignaturas más y examinarse de ellas a los 18 años. Estos exámenes se conocen con el nombre de A levels o Advanced levels. Cada universidad determina el número de A levels y la calificación necesaria para acceder a ella.
En Escocia los exámenes equivalentes son los Highers o Higher Grades, que se hacen de unas cinco asignaturas tras un año de estudios. Después se puede optar entre entrar en la universidad directamente o estudiar otro año más, bien para hacer el mismo examen de otras asignaturas, o para sacar los CSYS, abreviatura de Certificate of Sixth Year Studies.


2 [eɪ ə] INDEF ART (an (before vowel or silent h)) [æn ən n]
1.un(a) m/f; (+ fem noun starting with stressed a or ha) → un
a bookun libro
an appleuna manzana
a soulun alma
an eagleun águila
an axeun hacha
2. (article often omitted in translation)
2.1. (with professions) he is an engineeres ingeniero
I am not a doctoryo no soy médico
BUT he's a brilliant scientist → es un excelente científico
that child's a thief!¡ese niño es un ladrón!
2.2. (after tener/buscar if singular object the norm) I have a wife and six childrentengo mujer y seis hijos
have you got a passport?¿tiene usted pasaporte?
I haven't got a carno tengo coche
she's looking for a secretarybusca secretaria
BUT she has a daughter → tiene una hija
they have a lovely housetienen una casa preciosa LOOK FOR
2.3. (after negatives) you don't stand a chanceno tienes posibilidad alguna
without a doubtsin duda
without saying a wordsin decir palabra
2.4. (in expressions) half an hourmedia hora
a fine excuse!¡bonita disculpa!
what an idiot!¡qué idiota!
a hundred poundscien libras
a drink would be niceme gustaría algo de beber
2.5. (apposition) Patrick, a lecturer at Glasgow University, says thatPatrick, profesor de la Universidad de Glasgow, dice que ...
BUT the Duero, a Spanish river → el Duero, un río español
3. (= a certain) → un(a) tal
a Mr Smith called to see youvino a verte un tal señor Smith
4. (= each, per) → por
two apples a headdos manzanas por persona
£80 a week80 libras por semana
50 kilometres an hour50 kilómetros por hora
BUT 30 pence a kilo → 30 peniques el kilo
once a week/three times a monthuna vez a la semana/tres veces al mes


a [eɪ](STRONG) [ə]
(= letter) → A, a m
A for Alfa, A for Able (US)A comme Anatole
to get from A to B → aller d'un endroit à un autre
(= mark) (for essay, test)A, très bien dans le système éducatif britannique, note maximale pouvant être attribuée à un travail et qui équivaut dans le système français à une note comprise entre 16/20 et 20/20
(= musical note) A → la m A road, A shares


[eɪ](STRONG) [ə] an [ˈɑːn] (before vowel or mute h) indef art
a book → un livre
an apple → une pomme
he's a butcher → il est boucher
she's a doctor → elle est médecin
(instead of the number "one")un(e)
a year ago → il y a un an
a hundred pounds → cent livres
a thousand pounds → mille livres
(= per) (in expressing ratios, prices etc) 3 a day → 3 par jour
3 a week → 3 par semaine
once a week → une fois par semaine
10 km an hour → 10 km à l'heure
30 pence a kilo → trente pence le kilo


, a
nA nt, → a nt; (Sch: as a mark) → Eins f, → sehr gut; (Mus) → A nt, → a nt; from A to Zvon A bis Z; to get from A to Bvon A nach B kommen; A sharp (Mus) → Ais nt, → ais nt; A flat (Mus) → As nt, → as nt ? major


abbr of answerAntw.
(dated Brit Film) von der Filmkontrolle als nicht ganz jugendfrei gekennzeichneter Film A certificate Filmkennzeichnung, die Eltern vor dem nicht ganz jugendfreien Inhalt eines Films warnt


indef art before vowel <an>
ein(e); so large a schoolso eine große or eine so große Schule; a Mr Xein Herr X; a certain young manein gewisser junger Mann
(in negative constructions) not akein(e); not a single mankein einziger or nicht ein einziger Mann; he didn’t want a presenter wollte kein Geschenk
(with profession, nationality etc) he’s a doctor/Frenchmaner ist Arzt/Franzose; he’s a famous doctor/Frenchmaner ist ein berühmter Arzt/Franzose; as a young girlals junges Mädchen; a Washington would have …ein Washington hätte …
(= the same) to be of an age/a sizegleich alt/groß sein ? kind
(= per)pro; 50p a kilo50 Pence das or pro Kilo; twice a monthzweimal im or pro Monat; 50 km an hour50 Stundenkilometer, 50 Kilometer pro Stunde
in a good/bad moodgut/schlecht gelaunt; to come/to have come to an endzu Ende gehen/sein; in a loud voicemit lauter Stimme, laut; to have a headache/temperatureKopfschmerzen/erhöhte Temperatur haben


a [eɪ] n
a. (letter) → A, a f or m inv
A for Andrew (Am) A for Able → A come Ancona
to know sth from A to Z → sapere or conoscere qc dall'a alla zeta
to get from A to B → spostarsi da un punto all'altro
b. A9 (Brit) (road) → SS 9 =strada statale
c. (Mus) → la m inv
d. (Scol) (mark) → 10, ottimo


(ei) noun
one of the notes in the musical scale.
A flat (ˌei ˈflat) noun
(music) a note that is a semitone lower than A.
A sharp (ˌei ˈʃaːp) noun
(music) a note that is a semitone higher than A.



(ə(n)) indef. article
(a is used before words beginning with a consonant eg a boy, or consonant sound eg a union; an is used before words beginning with a vowel eg an owl, or vowel sound eg an honour.)
1. one. There is a boy in the garden.
2. any; every. An owl can see in the dark.
3. for each; per. We earn $6 an hour.

a before hotel, ~historian.
an before heir, ~honest, ~honour, ~hour.


اداة نكرة في الانجليزية ولا يعادلها شئ في العربية nějaký en/et ein ένας un un jedan un, uno 一つの 어떤 하나의 een en rodzajnik nieokreślony, nie tłumaczy się na język polski um en หนึ่ง bir một 一个