molecule
noun
mol·e·cule
ˈmä-li-ˌkyül 
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 honesty—
Time
TimeSynonyms
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
This briny water would have been an ideal place for new chemical reactions to take place and for organic molecules to form.
—Ars Technica, 30 Jan. 2025
Similar organic molecules, including amino acids, have been detected in meteorites before, but these fragments of space rocks are imperfect specimens because they are studied after enduring fiery trips through Earth's atmosphere.
—Denise Chow, NBC News, 29 Jan. 2025
What to Know Bennu, a carbon-rich asteroid formed as part of a parent body approximately 4.5 billion years ago, has long intrigued researchers due to its potential to harbor traces of water and organic molecules.
—Jonathan Granoff, Newsweek, 29 Jan. 2025
Fewer small molecule drugs will likely mean fewer cheaper generic versions of them on the market in the U.S., Eli Lilly’s Ricks said during the conference.
—Annika Kim Constantino, CNBC, 26 Jan. 2025
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Ars Technica, 30 Jan. 2025
Similar organic molecules, including amino acids, have been detected in meteorites before, but these fragments of space rocks are imperfect specimens because they are studied after enduring fiery trips through Earth's atmosphere.
—Denise Chow, NBC News, 29 Jan. 2025
What to Know Bennu, a carbon-rich asteroid formed as part of a parent body approximately 4.5 billion years ago, has long intrigued researchers due to its potential to harbor traces of water and organic molecules.
—Jonathan Granoff, Newsweek, 29 Jan. 2025
Fewer small molecule drugs will likely mean fewer cheaper generic versions of them on the market in the U.S., Eli Lilly’s Ricks said during the conference.
—Annika Kim Constantino, CNBC, 26 Jan. 2025
See all Example Sentences for molecule
Articles Related to molecule
Dictionary Entries Near molecule
Cite this Entry
“Molecule.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/molecule. Accessed 9 Feb. 2025.
Copy CitationKids Definition
molecule
noun
mol·e·cule
ˈmäl-i-ˌkyü(ə)l
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
: 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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