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 adjective

Examples of double helix in a Sentence

Recent Examples on the Web 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 Li says that her book is structured like a double helix, with her personal quest and the trajectory of AI intertwined into a spiraling whole. Steven Levy, WIRED, 13 Sep. 2024 One of the challenges of working with ancient DNA samples is that damage accumulates over time, breaking up the structure of the double helix into ever smaller fragments. John Timmer, Ars Technica, 11 July 2024 Her first breakthrough came in 1956, just three years after the double helix structure of DNA was understood. Brian Murphy, Washington Post, 10 July 2024 See all Example Sentences for double helix 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'double helix.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1954, in the meaning defined above

Time Traveler
The first known use of double helix was in 1954

Dictionary Entries Near double helix

Cite this Entry

“Double helix.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/double%20helix. Accessed 9 Oct. 2024.

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 adjective

More from Merriam-Webster on double helix

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