the simplest unit of a chemical compound that can exist, consisting of two or more atoms held together by chemical bonds a very small particle
WordReference Random House Learner's Dictionary of American English © 2026
mol•e•cule /ˈmɑləˌkyul/USA pronunciation
n. [countable]
WordReference Random House Unabridged Dictionary of American English © 2026- Chemistry, Physicsthe smallest physical unit of an element or compound, made up of one or more similar atoms in an element and two or more different atoms in a compound.
- any very small particle.
mol•e•cule
(mol′ə kyo̅o̅l′),USA pronunciation n.
- Chemistry, Physicsthe smallest physical unit of an element or compound, consisting of one or more like atoms in an element and two or more different atoms in a compound.
- Chemistrya quantity of a substance, the weight of which, measured in any chosen unit, is numerically equal to the molecular weight;
gram molecule. - any very small particle.
- Neo-Latin, equivalent. to Latin mōlē(s) mass + -cula -cule1
- earlier molecula 1785–95
Collins Concise English Dictionary © HarperCollins Publishers::
'molecule' also found in these entries (note: many are not synonyms or translations):
-cule
- Avogadro's number
- C terminus
- D, d
- DNA
- DNase
- Goldschmidt
- acid radical
- activate
- adsorb
- alkaloid
- alpha
- amphipathic
- antibody
- asymmetric
- atomicity
- base
- benzene ring
- binary
- binding energy
- biogen
- blood-brain barrier
- bond
- bridge
- buckyball
- cDNA
- capture
- chain
- chelate
- chemiluminescence
- chemoreceptor
- chiral
- clathrate
- cleavage
- codon
- coenzyme
- communication
- complex
- condensation
- configuration
- conformation
- conjugation
- constitutive
- corepressor
- covalency
- crack
- critical volume
- cross-link
- degradation
- degree of freedom