: 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

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
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Days later, a forensic biologist found that Lin's blood and DNA were found all over Magnotta's apartment. Jessica Sager, People.com, 25 May 2025 Semler sued in federal court in Orlando in 2019, alleging the clinic had made 49 clones of Milly without permission to make money off the diminutive dog’s DNA. Stephen Hudak, The Orlando Sentinel, 24 May 2025 Experts believe that changes in the DNA of bone marrow cells cause AML.1 DNA is genetic material that tells the cells how to grow and function. Health, 24 May 2025 Monroy-Lara fled to California and was later identified by DNA from a condom wrapper, the court filing said. Sara Schilling, Sacbee.com, 23 May 2025 See All Example Sentences for DNA

Word History

Etymology

deoxyribonucleic acid

First Known Use

1944, in the meaning defined above

Time Traveler
The first known use of DNA was in 1944

Browse Nearby Words

Cite this Entry

“DNA.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/DNA. Accessed 29 May. 2025.

Kids Definition

: 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

: 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

More from Merriam-Webster on DNA

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