double helix

noun

: a helix or spiral consisting of two strands in the surface of a cylinder that coil around its axis

especially : the structural arrangement of DNA in space that consists of paired polynucleotide strands stabilized by cross-links between purine and pyrimidine bases compare alpha-helix, watson-crick model

double-helical

ˌdə-bəl-ˈhe-li-kəl 

-ˈhē-

adjective

Examples of double helix in a Sentence

Recent Examples on the Web

This elegant double helix of a novel entwines the stories of a fictional modern-day British girl and a real-life 15th-century Italian painter. —New York Times, 8 July 2024

If that atom happens to be part of a DNA molecule, the result can be a breakage in one or both of the delicate strands that wind into the famous double helix. —Tom Hawking, Popular Science, 24 Oct. 2024

Photograph: Peter Fisher At one point, Bailey sketched an idea around a double helix shape. —Joseph Bien-Kahn, WIRED, 19 Sep. 2024

The key shows the universal elements (hydrogen, oxygen, carbon and nitrogen), the four bases of the DNA molecule (adenine, cytosine, guanine and thymine) with their molecular structure, where they’re placed in the DNA double helix, and how genes are arranged on a chromosome. —New Atlas, 19 Sep. 2024

Word History

First Known Use

1954, in the meaning defined above

Kids Definition

double helix

noun

: the arrangement in space of DNA that resembles a spirally twisted ladder with the sides made up of the sugar and phosphate units of the two nucleotide strands and the rungs made up of the pyrimidine and purine bases extending into the center and joined by hydrogen bonds

Medical Definition

double helix

noun

: a helix or spiral consisting of two strands in the surface of a cylinder that coil around its axis

especially : the structural arrangement of DNA in space that consists of paired polynucleotide strands stabilized by cross-links between purine and pyrimidine bases compare alpha-helix, watson-crick model

double-helical

-ˈhel-i-kəl  -ˈhē-li- 

adjective