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).]
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.
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]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
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]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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.
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.
atom
The smallest part of an element capable of taking part in a chemical change.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
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| Noun | 1. |  atom - (physics and chemistry) the smallest component of an element having the chemical properties of the elementsubstance - 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 anythinggrain - 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 |
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
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
Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition. 2002 © HarperCollins Publishers 1995, 2002
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
B. CPD atom bomb N → bomba f atómica
atom smasher N → acelerador m de partículas atómicas, rompeátomos m inv
atom smasher N → acelerador m de partículas atómicas, rompeátomos m inv
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
Collins English/French Electronic Resource. © HarperCollins Publishers 2005
atom
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995
atom
(ˈӕtəm) noun1. the smallest part of an element.
2. anything very small. There's not an atom of truth in what she says.
aˈtomic (-ˈto-) adjectiveatom(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.
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.
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Multilingual Translator © HarperCollins Publishers 2009
at·om
n. átomo.
English-Spanish Medical Dictionary © Farlex 2012