adenine

noun

ad·​e·​nine ˈa-də-ˌnēn 

: a purine base C₅H₅N₅ that codes hereditary information in the genetic code in DNA and RNA compare cytosine, guanine, thymine, uracil

Examples of adenine in a Sentence

Recent Examples on the Web

Scientists have discovered that a sample of the Ryugu asteroid collected by Japan's Hayabusa 2 spacecraft contains the nucleobases adenine, guanine, cytosine, thymine and uracil, the building blocks of DNA and RNA upon which all life is based. —Robert Lea, Space.com, 17 Mar. 2026

Those rungs are made up of pairs of four different chemical building blocks, called bases — adenine, thymine, cytosine and guanine (A,T,C and G). —F.d. Flam, Mercury News, 26 Nov. 2025

There are four different bases: adenine (A), guanine (G), cytosine (C), and thymine (T). —IEEE Spectrum, 2 Oct. 2025

Biology’s four bases—adenine (A), thymine (T), cytosine (C) and guanine (G)—encode the instructions that keep life alive. —Andrew Whalen, Forbes.com, 9 July 2025

Word History

Etymology

borrowed from German Adenin, from Greek aden-, adḗn "gland" + German -in -ine entry 2; so called from its presence in glandular tissue — more at adeno-

First Known Use

1885, in the meaning defined above

Phrases Containing adenine

• flavin adenine dinucleotide
• nicotinamide adenine dinucleotide
• nicotinamide adenine dinucleotide phosphate

Rhymes for adenine

• acrolein
• alkylene
• aniline
• anthracene
• aquiline
• asphaltene
• atlantean
• atrazine
• butadiene
• butylene
• caesarean
• carnitine

Kids Definition

adenine

noun

ad·​e·​nine ˈad-ᵊn-ēn 

: one of the bases which make up the genetic code of DNA and RNA compare cytosine, guanine, thymine, uracil

Medical Definition

adenine

noun

ad·​e·​nine ˈad-ᵊn-ˌēn 

: a purine base C₅H₅N₅ that codes hereditary information in the genetic code in DNA and RNA compare cytosine, guanine, thymine, uracil