peptide

noun

pep·​tide ˈpep-ˌtīd How to pronounce peptide (audio)
: any of various amides that are derived from two or more amino acids by combination of the amino group of one acid with the carboxyl group of another and are usually obtained by partial hydrolysis of proteins
peptidic
pep-ˈti-dik How to pronounce peptide (audio)
adjective

Examples of peptide in a Sentence

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.
People are buying a peptide called retatrutide online to lose weight. — Shane O’Neill, Washington Post, 2 July 2026 The formula includes peptides and ceramides to protect against external aggressors and restore the skin barrier. — Reece Andavolgyi, InStyle, 4 July 2026 Designed to help renew and revive skin, paired with skin-lifting actives and anti-wrinkle peptides that penetrate the skin’s surface to boost collagen, even texture, and smooth fine lines. — ABC News, 6 July 2026 The skin isn’t just a passive barrier that accepts humectants, peptides, and other ingredients and keeps out external aggressors like pollutants and bacteria. — Deanna Pai, Vogue, 6 July 2026 See All Example Sentences for peptide

Word History

Etymology

International Scientific Vocabulary, from peptone

First Known Use

1906, in the meaning defined above

Time Traveler
The first known use of peptide was in 1906

Phrases Containing peptide

Rhymes for peptide

See All Rhymes for peptide

Browse Nearby Words

peptidase
peptide
peptide bond
See all Nearby Words

Cite this Entry

“Peptide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/peptide. Accessed 8 Jul. 2026.

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Kids Definition

peptide

noun
pep·​tide ˈpep-ˌtīd How to pronounce peptide (audio)
: any of various substances that are usually obtained by the partial breakdown of proteins

Medical Definition

peptide

noun
pep·​tide ˈpep-ˌtīd How to pronounce peptide (audio)
: any of various amides that are derived from two or more amino acids by combination of the amino group of one acid with the carboxyl group of another and are usually obtained by partial hydrolysis of proteins
peptidic
pep-ˈtid-ik How to pronounce peptide (audio)
adjective

More from Merriam-Webster on peptide

Britannica.com: Encyclopedia article about peptide

Last Updated: - Updated example sentences
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