peptide

American

[pep-tahyd] / ˈpɛp taɪd /

noun

Biochemistry.

a compound containing two or more amino acids in which the carboxyl group of one acid is linked to the amino group of the other.

peptide British

/ ˈpɛptaɪd /

noun

any of a group of compounds consisting of two or more amino acids linked by chemical bonding between their respective carboxyl and amino groups See also peptide bond polypeptide

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

peptide Scientific

/ pĕp′tīd′ /

A chemical compound that is composed of a chain of two or more amino acids and is usually smaller than a protein. The amino acids can be alike or different. Many hormones and antibiotics are peptides.

Etymology

Origin of peptide

1905–10; pept(ic) + -ide ( def. )

Compare meaning

How does peptide compare to similar and commonly confused words? Explore the most common comparisons:

peptide vs. polypeptide

Vocabulary lists containing peptide

Nutrition and Digestion - High School

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Among so-called peptide users, often people involved in the fitness or looksmaxxing communities, off-label use of retatrutide has become popular.

From MarketWatch • May 21, 2026

In the US, the FDA is considering easing restrictions on the use of peptide injections after Health Secretary Robert F Kennedy Jr pushed to have the therapies deregulated.

From BBC • May 20, 2026

The reversal is good news for Hims, which has indicated it is looking to enter the peptide business.

From Barron's • May 11, 2026

“Foremost, they should be talking to their doctors,” said Dr. Adda Grimberg, a pediatric endocrinologist and scientific director of the Growth Center at Children’s Hospital of Philadelphia, of teen peptide use.

From The Wall Street Journal • May 11, 2026

Pauling had cracked the a-helix by ruthlessly following up his knowledge that the peptide bond was flat.

From "Double Helix" by James D. Watson

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023