DNA

noun

ˌdē-ˌen-ˈā 

: any of various nucleic acids that are usually the molecular basis of heredity, are constructed of a double helix held together by hydrogen bonds between purine and pyrimidine bases (see base entry 1 sense 6b) which project inward from two chains containing alternate links of deoxyribose and phosphate, and that in eukaryotes are localized chiefly in cell nuclei compare recombinant dna

Illustration of DNA

• A molecular model
• 1 hydrogen
• 2 oxygen
• 3 carbon in the helical phosphate ester chains
• 4 carbon and nitrogen in the cross-linked purine and pyrimidine bases
• 5 phosphorus
• B double helix

Examples of DNA in a Sentence

Recent Examples on the Web

From the beginning, MRT has been the subject of ethical controversy because of the unknown health risks of exposing unborn children to any amount of donor DNA. — Megan Molteni, STAT, 2 Nov. 2026

Jimbo also worked as co-director of the MCA DNA Research Initiative, a multiyear program that commissioned interdisciplinary scholarship, digital content, and public programs focused on the museum’s collection and archives. — News Desk, Artforum, 2 Nov. 2026

In ways sometimes obvious, sometimes subtle, much of his art over the years has Bruce Goff in its DNA. — Web Behrens, Chicago Tribune, 2 Nov. 2026

Last year, her play Mother’s Day debuted as part of the DNA New Works Program at La Jolla Playhouse, and her play The Cake has been produced more than 100 times globally. — Greg Evans, Deadline, 2 Nov. 2026

Word History

Etymology

deoxyribonucleic acid

First Known Use

1944, in the meaning defined above

Phrases Containing DNA

• DNA fingerprinting
• DNA methylation
• DNA phenotyping
• DNA polymerase
• DNA test
• DNA virus
• junk DNA
• mitochondrial DNA
• recombinant DNA
• satellite DNA

Rhymes for DNA

• ay
• bay
• bey
• brae
• cay
• chez
• dey
• dray
• fay
• fey
• flay
• fray

Kids Definition

DNA

noun

ˌdē-ˌen-ˈā 

: any of various nucleic acids that are located especially in cell nuclei, are usually the chemical basis of heredity, and are composed of two nucleotide chains held together by hydrogen bonds in a pattern resembling a flexible twisted ladder compare rna

Medical Definition

DNA

noun

ˌdē-ˌen-ˈā 

: any of various nucleic acids that are usually the molecular basis of heredity, are constructed of a double helix held together by hydrogen bonds between purine and pyrimidine bases which project inward from two chains containing alternate links of deoxyribose and phosphate, and that in eukaryotes are localized chiefly in cell nuclei

called also deoxyribonucleic acid

see recombinant dna