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(word root) not, from
Examples of words with the root a-: asexual, atheist
Abused, Confused, & Misused Words by Mary Embree Copyright © 2007, 2013 by Mary Embree

a- 1

or an-
Without; not: amoral.

[Greek; see ne in Indo-European roots.]

a- 2

1. On; in: abed.
2. In the act of: aborning.
3. In the direction of: astern.
4. In a specified state or condition: abuzz.

[Middle English, from Old English, from an, on; see on.]
Our Living Language Prefixing a- to verb forms ending in -ing, as in a-hunting and a-fishing, was once fairly common in vernacular US speech, particularly in the highland areas of the South and in the Southwest. Such verb forms derive from an Old English construction in which a preposition, usually on, was placed in front of a verbal noun—a verb to which -ing had been added to indicate that the action was extended or ongoing. Gradually such prepositions were shortened to a-. The -ing forms came to be regarded as present participles rather than verbal nouns, and the use of a- was extended to genuine present participles. Eventually a- disappeared from many dialects, including Standard English in the United States and Great Britain, although it is still retained today in some isolated dialect areas. Today, speakers who use the a- prefix do not use it randomly. Rather, a- is only used with -ing words that begin with a consonant, have stress on the first syllable, and function as part of a verb phrase, as in She was a-running.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


or before a vowel


not; without; opposite to: atonal; asocial.
[from Greek a-, an- not, without]


1. on; in; towards: afoot; abed; aground; aback.
2. literary or archaic (used before a present participle) in the act or process of: come a-running; go a-hunting.
3. in the condition or state of: afloat; alive; asleep.
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

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.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


A prefix meaning "without" or "not" when forming an adjective (such as amorphous, without form, or atypical, not typical), and "absence of" when forming a noun (such as arrhythmia, absence of rhythm). Before a vowel or h it becomes an- (as in anhydrous, anoxia).
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


PREFIX (archaic or dial) everyone came a-runningtodos acudieron corriendo
it was a-snowing hardestaba nevando mucho
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


(privative) amoralamoralisch; atypicalatypisch
(old, dial) they came a-runningsie kamen angerannt; the bells were a-ringingdie Glocken läuteten
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007