mol·​e·​cule | \ ˈmä-li-ˌkyül How to pronounce molecule (audio) \

Definition of molecule

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 Forrest has yet to produce a molecule of hydrogen and a recent flurry of announcements are far from firm contracts... Zach Everson, Forbes, 24 June 2022 And early research shows that a small group of people have a genetic flaw that cripples a crucial immune molecule called interferon type I, putting them at higher risk of severe Covid symptoms. New York Times, 11 June 2022 While a majority of pancreatic cancers have a KRAS mutation, Tran said that just about 4 percent of pancreatic cancer patients have the mutation as well as a specific molecule on the cell surface necessary to be eligible for this particular therapy. Reynolds Lewis, NBC News, 2 June 2022 By identifying a specific molecule that was responsible for the accumulation of those wacky proteins, the lab now had a lead on a possible target for treatment. Isabella Cueto, STAT, 2 May 2022 This super-thick cream has 30% concentration of proxylane, a sugar molecule that keeps skin plump and hydrated. ELLE, 28 Apr. 2022 The new work aims to create a single molecule that acts as a bridge between graphene and molybdenum disulfide. John Timmer, Ars Technica, 27 Apr. 2022 Made with a special bio-identical wound-healing molecule never before used in a body moisturizer, the luxe formula produced visible skin benefits. April Franzino, Good Housekeeping, 26 Apr. 2022 AirCarbon material—a new alternative to leather—involves marine organisms that convert methane and carbon dioxide into a molecule that can then be melted down. Emily Chan, Vogue, 22 Apr. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'molecule.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of molecule

1701, in the meaning defined at sense 1

History and Etymology for molecule

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

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Time Traveler for molecule

Time Traveler

The first known use of molecule was in 1701

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Dictionary Entries Near molecule

molecular weight



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Last Updated

1 Jul 2022

Cite this Entry

“Molecule.” Dictionary, Merriam-Webster, Accessed 2 Jul. 2022.

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More Definitions for molecule


mol·​e·​cule | \ ˈmä-li-ˌkyül How to pronounce molecule (audio) \

Kids Definition of molecule

: the smallest portion of a substance having the properties of the substance a molecule of water


mol·​e·​cule | \ ˈmäl-i-ˌkyü(ə)l How to pronounce molecule (audio) \

Medical Definition of molecule

: 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

Nglish: Translation of molecule for Spanish Speakers

Britannica English: Translation of molecule for Arabic Speakers Encyclopedia article about molecule


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