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ATOM
| Pronunciation (US): |  | (GB): | |
I. (noun)
Sense 1
Meaning:
(nontechnical usage) a tiny piece of anything
Synonyms:
atom; corpuscle; molecule; mote; particle; speck
Classified under:
Hypernyms ("atom" is a kind of...):
material; stuff (the tangible substance that goes into the makeup of a physical object)
Hyponyms (each of the following is a kind of "atom"):
grain (a relatively small granular particle of a substance)
grinding (material resulting from the process of grinding)
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)
Derivation:
atomic (immeasurably small)
atomise (break up into small particles)
Sense 2
Meaning:
(physics and chemistry) the smallest component of an element having the chemical properties of the element
Classified under:
Nouns denoting substances
Hypernyms ("atom" is a kind of...):
substance (the real physical matter of which a person or thing consists)
Meronyms (parts of "atom"):
nucleus (the positively charged dense center of an atom)
elementary particle; fundamental particle ((physics) a particle that is less complex than an atom; regarded as constituents of all matter)
Domain category:
natural philosophy; physics (the science of matter and energy and their interactions)
chemical science; chemistry (the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions)
Hyponyms (each of the following is a kind of "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)
carbon atom (an atom of carbon)
hydrogen atom (an atom of hydrogen)
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)
Holonyms ("atom" is a part of...):
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)
molecule ((physics and chemistry) the simplest structural unit of an element or compound)
Derivation:
atomic (of or relating to or comprising atoms)
atomise (break up into small particles)
atomise (spray very finely)
atomize (break up into small particles)
Context examples:
Ultimately, the atoms in a large galaxy, like those around us, could have originally come from up to a million light-years away.
(Half Our Body's Atoms Could Have Come from Outside The Galaxy, The Titi Tudorancea Bulletin)
For example, the molecular weight of water, which has two atoms of hydrogen and one atom of oxygen, is 18 (i.e., 2 + 16).
(Molecular weight, NCI Dictionary)
Water is also known by its chemical name H2O because it's made of two hydrogen atoms and one oxygen atom.
(Comet Provides New Clues to Origins of Earth's Oceans, NASA)
Alcohols are classified according to the position of the carbon atom with the attached hydroxyl group (i.e. primary alcohols are alcohols with the OH group attached to the primary carbon atom, C1).
(Alcohol [Chemical Class], NCI Thesaurus)
Alcohol contains a carbon atom attached to a hydroxyl group (a molecule made of an oxygen atom and a hydrogen atom).
(Alcohol, NCI Dictionary)
A small molecule made of two carbon, three hydrogen, and one oxygen atoms.
(Acetyl group, NCI Dictionary)
Chirality axis based stereochemistry where, using the Cahn-Ingold-Prelog (CIP) priority rules, the priorities (from highest to lowest) of the substituent atoms exist in a counterclockwise direction.
(Axial S, NCI Thesaurus)
A sterol derivative of cholesterol with two nitrogen atoms replacing two carbon atoms that acts as a hypocholesteremic agent by blocking delta-24-reductase.
(Azacosterol, NCI Thesaurus)
It is the amount of substance that contains as many elementary units as there are atoms in 0.012 kg of carbon-12.
(Mole, NCI Thesaurus)
These enzymes use molecular oxygen catalyze the donation of one oxygen atom to a substrate specific site, while the other atom is donated to the generation of water.
(Mixed Function Oxidase, NCI Thesaurus)
