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

Premiering Thursday night on HBO and BBC, the show follows the destructive, codependent 30-year bond between two brothers-in-all-but-DNA, Ruben (Gadd) and Niall (Jamie Bell). —Lexi Carson, HollywoodReporter, 23 Apr. 2026

This method bore fruit, with a close relative of the DNA identified in 2025. —Flint McColgan, Boston Herald, 23 Apr. 2026

Respect for the environment sits at the heart of Tella Thera’s DNA, with bioclimatic architecture, property-wide sustainability smarts and a low-waste restaurant where dishes brim with island produce. —Condé Nast, Condé Nast Traveler, 23 Apr. 2026

Ong sees wind as a natural extension of the company’s engineering DNA. —Nicholas Gordon, Fortune, 23 Apr. 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