atom


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at·om

 (ăt′əm)
n.
1.
a. A part or particle considered to be an irreducible constituent of a specified system.
b. The irreducible, indestructible material unit postulated by ancient atomism.
2. An extremely small part, quantity, or amount.
3. Physics & Chemistry
a. The smallest unit of an element, having all the characteristics of that element and consisting of a very small and dense central nucleus containing protons and neutrons, surrounded by one or more shells of orbiting electrons. Atoms remain undivided in chemical reactions except for the donation, acceptance, or exchange of valence electrons.
b. This unit regarded as a source of nuclear energy.

[Middle English attome, from Latin atomus, from Greek atomos, indivisible, atom : a-, not; see a-1 + tomos, cutting (from temnein, to cut; see tem- in Indo-European roots).]

atom

(ˈætəm)
n
1. (Atomic Physics)
a. the smallest quantity of an element that can take part in a chemical reaction
b. this entity as a source of nuclear energy: the power of the atom. See also atomic structure
2. any entity regarded as the indivisible building block of a theory
3. (Philosophy) the hypothetical indivisible particle of matter postulated by certain ancient philosophers as the fundamental constituent of matter. See also atomism
4. a very small amount or quantity; minute fragment: to smash something to atoms; there is not an atom of truth in his allegations.
[C16: via Old French and Latin, from Greek atomos (n), from atomos (adj) that cannot be divided, from a-1 + temnein to cut]

at•om

(ˈæt əm)

n.
1. the smallest component of an element having the chemical properties of the element, consisting of a positively charged nucleus of neutrons and protons that exerts an electrical attraction on one or more electrons in motion around it.
2. this component as the source of nuclear energy.
3. a hypothetical particle of matter so minute as to admit of no division.
4. anything extremely small; a minute quantity; speck; scintilla: not an atom of truth in that statement.
[1350–1400; < Latin atomus < Greek átomos literally, undivided =a- a-6 + -tomós divided <témnein to cut]
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at·om

(ăt′əm)
The smallest unit of an element, consisting of protons and neutrons in a dense central nucleus orbited by a number of electrons. In electrically neutral atoms, the number of protons equals the number of electrons. Atoms remain intact in chemical reactions except for the removal, transfer, or exchange of certain electrons. See Note at subatomic particle.

atom

The smallest part of an element capable of taking part in a chemical change.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.atom - (physics and chemistry) the smallest component of an element having the chemical properties of the elementatom - (physics and chemistry) the smallest component of an element having the chemical properties of the element
substance - the real physical matter of which a person or thing consists; "DNA is the substance of our genes"
chemical science, chemistry - the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions
natural philosophy, physics - the science of matter and energy and their interactions; "his favorite subject was physics"
elementary particle, fundamental particle - (physics) a particle that is less complex than an atom; regarded as constituents of all matter
nucleus - the positively charged dense center of an atom
isotope - one of two or more atoms with the same atomic number but with different numbers of neutrons
monad - (chemistry) an atom having a valence of one
chemical element, element - any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter
carbon atom - an atom of carbon
hydrogen atom - an atom of hydrogen
molecule - (physics and chemistry) the simplest structural unit of an element or compound
free radical, radical - an atom or group of atoms with at least one unpaired electron; in the body it is usually an oxygen molecule that has lost an electron and will stabilize itself by stealing an electron from a nearby molecule; "in the body free radicals are high-energy particles that ricochet wildly and damage cells"
2.atom - (nontechnical usage) a tiny piece of anythingatom - (nontechnical usage) a tiny piece of anything
grain - a relatively small granular particle of a substance; "a grain of sand"; "a grain of sugar"
grinding - material resulting from the process of grinding; "vegetable grindings clogged the drain"
material, stuff - the tangible substance that goes into the makeup of a physical object; "coal is a hard black material"; "wheat is the stuff they use to make bread"
chylomicron - a microscopic particle of triglycerides produced in the intestines during digestion; in the bloodstream they release their fatty acids into the blood
flyspeck - a tiny dark speck made by the excrement of a fly
identification particle - a tiny particle of material that can be added to a product to indicate the source of manufacture

atom

noun particle, bit, spot, trace, scrap, molecule, grain, dot, fragment, fraction, shred, crumb, mite, jot, speck, morsel, mote, whit, tittle, iota, scintilla (rare) one carbon atom attached to four hydrogens
Translations
ذَرَّهذَرَّةمِقْدار ضَئيل جِداً
atomzrnko
atomgran
aatom
atomi
atom
atom
atóm, frumeindsnefill
原子元素
원자
atomasatominė energijaatominisdalelė
atomsdruska
atóm
atom
atom
อะตอม
nguyên tử

atom

[ˈætəm]
A. N
1. (Phys) → átomo m
2. (fig) → pizca f
there is not an atom of truth in iteso no tiene ni pizca de verdad
if you had an atom of sensesi tuvieras una gota de sentido común
to smash sth to atomshacer algo añicos
B. CPD atom bomb Nbomba f atómica
atom smasher Nacelerador m de partículas atómicas, rompeátomos m inv

atom

[ˈætəm] n (PHYSICS)atome matom bomb n (mainly British)bombe f atomique

atom

n
Atom nt
(fig) to powder something into atomsetw völlig zertrümmern; not an atom of truthkein Körnchen Wahrheit

atom

[ˈætəm] natomo (fig) not an atom of truthnemmeno un pizzico di verità

atom

(ˈӕtəm) noun
1. the smallest part of an element.
2. anything very small. There's not an atom of truth in what she says.
aˈtomic (-ˈto-) adjective
atom(ic) bomb
a bomb using atomic energy.
atomic energy
very great energy obtained by breaking up the atoms of some substances.
atomic power
power (for making electricity etc) obtained from atomic energy.

atom

ذَرَّة atom atom Atom άτομο átomo atomi atome atom atomo 原子 원자 atoom atom atom átomo атом atom อะตอม atom nguyên tử 原子

at·om

n. átomo.
References in classic literature ?
Meg thought it was too cruel to hint about her sad failure, and the last atom of patience vanished as he spoke.
not the smallest atom stirs or lives on matter, but has its cunning duplicate in mind.
And as for me, all that I think about in this plodding sad pilgrimage, this pathetic drift between the eternities, is to look out and humbly live a pure and high and blameless life, and save that one microscopic atom in me that is truly ME: the rest may land in Sheol and welcome for all I care.
Every atom of your flesh is as dear to me as my own: in pain and sickness it would still be dear.
One state resembles setting a hungry man down to a single dish, on which he may concentrate his entire appetite and do it justice; the other, introducing him to a table laid out by French cooks: he can perhaps extract as much enjoyment from the whole; but each part is a mere atom in his regard and remembrance.
His face looked dreadful, white and red and swollen, and he was gasping and choking; but savage little Mary did not care an atom.
Eked out by apple-sauce and mashed potatoes, it was a sufficient dinner for the whole family; indeed, as Mrs Cratchit said with great delight (surveying one small atom of a bone upon the dish), they hadn't ate it all at last.
All the rest of that day, and from morning to night afterwards, she sat at that desk, scratching composedly with a hard pen, speaking in the same imperturbable whisper to everybody; never relaxing a muscle of her face, or softening a tone of her voice, or appearing with an atom of her dress astray.
Nay, without thought or conscious desire, might not things external to ourselves vibrate in unison with our moods and passions, atom calling to atom in secret love or strange affinity?
The jury all wrote down on their slates, `SHE doesn't believe there's an atom of meaning in it,' but none of them attempted to explain the paper.
Directly in front of him, holding on by a low branch, stood a naked brown baby who could just walk--as soft and as dimpled a little atom as ever came to a wolf's cave at night.
The average time, for instance, taken to reply to a telephone call by a New York operator, is now three and two-fifth seconds; and even this tiny atom of time is being strenuously worn down.