thymine

American

[thahy-meen, -min] / ˈθaɪ min, -mɪn /

noun

Biochemistry.

a pyrimidine base, C 5 H 6 N 2 O 2 , that is one of the principal components of DNA, in which it is paired with adenine. T

thymine British

/ ˈθaɪmiːn /

noun

a white crystalline pyrimidine base found in DNA. Formula: C 5 H 6 N 2 O 2

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

thymine Scientific

/ thī′mēn′ /

A pyrimidine base that is a component of DNA. It forms a base pair with adenine. Chemical formula: C ₅ H ₆ N ₂ O ₂ .

Etymology

Origin of thymine

First recorded in 1890–95; thym(ic) ² + -ine ²

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Vocabulary lists containing thymine

Genetics - Middle School

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Example Sentences

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Importantly they also discovered all five nitrogenous bases — adenine, guanine, cytosine, thymine, and uracil — that are necessary to build DNA and RNA.

From Salon • Jan. 30, 2025

These include 14 of the 20 amino acids that life on Earth uses to build proteins and all four of the ring-shaped molecules that make up DNA - adenine, guanine, cytosine and thymine.

From BBC • Jan. 29, 2025

Nucleotides are composed of three distinctive parts: a sugar molecule, a phosphate group and one of the four nucleobases adenine, thymine, guanine and cytosine.

From Science Daily • Mar. 8, 2024

For example, exposure to water can cause a chemical reaction called deamination that changes the nucleotide cytosine such that it appears to be the nucleotide thymine upon analysis.

From Scientific American • Aug. 25, 2023

“Suddenly I became aware that an adenine thymine pair was identical in shape to a guanine cytosine pair...no fudging was required to make the two types of base pairs identical in shape.”

From "The Gene" by Siddhartha Mukherjee

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023