molecule

noun

mol·​e·​cule ˈmä-li-ˌkyül How to pronounce molecule (audio)
Synonyms of moleculenext
1
: the smallest particle of a substance that retains all the properties (see property sense 1a) of the substance and is composed of one or more atoms (see atom sense 1a)
a molecule of water
a molecule of oxygen
2
: a tiny bit : particle
There is a molecule of evidence to support these charges.

Synonyms of molecule

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Examples of molecule in a Sentence

There is not a molecule of evidence to support these charges. not a molecule of sense in that girl
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The antibodies created from the reaction learned to identify and attack alpha-gal sugar molecules, making meat from mammals toxic to his system. — Dylan Lovan, Fortune, 6 Sep. 2026 Empa Empa's underlying epoxy chemistry uses reactive phosphorus-containing molecules to introduce dynamic bonds into the thermoset. — New Atlas, 6 Sep. 2026 Teaching computers how molecules behave Rather than relying entirely on a long cycle of synthesis, measurement and redesign, the researchers want to build computational tools that can identify promising molecular arrangements in advance. — Rupendra Brahambhatt, Interesting Engineering, 5 Sep. 2026 Preclinical research also suggests that quinoa saponins may reduce the production of inflammatory mediators and pro-inflammatory molecules. — Amy Brownstein, Verywell Health, 4 Sep. 2026 See All Example Sentences for molecule

Word History

Etymology

French molécule, from New Latin molecula, diminutive of Latin moles mass

First Known Use

1701, in the meaning defined at sense 1

Time Traveler
The first known use of molecule was in 1701

Rhymes for molecule

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Browse Nearby Words

molecular weight
molecule
moled
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Cite this Entry

“Molecule.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/molecule. Accessed 7 Sep. 2026.

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Kids Definition

molecule

noun
mol·​e·​cule ˈmäl-i-ˌkyü(ə)l How to pronounce molecule (audio)
1
: the smallest particle of a substance having all the characteristics of the substance
a molecule of water
a molecule of oxygen
2
: a very small bit : particle

Medical Definition

molecule

noun
mol·​e·​cule ˈmäl-i-ˌkyü(ə)l How to pronounce molecule (audio)
: the smallest particle of a substance that retains all the properties of the substance and is composed of one or more atoms

More from Merriam-Webster on molecule

Britannica.com: Encyclopedia article about molecule

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