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

Crooks was not carrying identification, so he was identified via DNA, CBS News previously reported. — Angel Saunders, PEOPLE, 25 Sep. 2026

Both of these regions featured different chromatin — a mixture of DNA, RNA, and proteins that packages long DNA molecules — setting them on independent developmental paths. — Victor Tangermann, Futurism, 24 Sep. 2026

The formula is infused with niacinamide, vitamin C, a peptide complex, hydrolyzed collagen, and salmon DNA, which explains why my skin always looks brighter, feels pillow soft, and has the elasticity of a rubber band. — Essence Wiley, InStyle, 24 Sep. 2026

Cozzi’s blood was found in the bed of Kosowski’s pickup truck and on a ballistic vest in the trunk of Kosowski’s second car, DNA results submitted at trial confirmed. — Lauren Del Valle, CNN Money, 23 Sep. 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