molecule

noun

mol·​e·​cule ˈmä-li-ˌkyül How to pronounce molecule (audio)
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
a molecule of political honestyTime

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.
Faster movement of air molecules produces a higher temperature, and slower movement results in lower temperatures. Mary Wasson, Austin American Statesman, 24 July 2025 Just as the Statue of Zeus represented wisdom and power, AI has noble applications across healthcare, including unraveling the complexities of biological systems where billions of molecules work together to drive the human body. Dean Debiase, Forbes.com, 23 July 2025 Antioxidants counter destructive free radical molecules in cells, acting to reduce inflammation and the risk of chronic disease. Angelica Bottaro, Verywell Health, 23 July 2025 The touch of the grill is felt in every corner of the room, like a high-sillage perfume made of the primal, appetite-turbocharging molecules of smoke and meat and sweetness. Helen Rosner, New Yorker, 20 July 2025 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

Browse Nearby Words

Cite this Entry

“Molecule.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/molecule. Accessed 29 Jul. 2025.

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

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