thymine

American  

[thahy-meen, -min] / ˈθaɪ min, -mɪn /

noun

Biochemistry.

1. 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

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thymine British  

/ ˈθaɪmiːn /

noun

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

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thymine Scientific  

/ thī′mēn′ /

1. 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 .

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Etymology

Origin of thymine

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

Compare meaning

How does thymine compare to similar and commonly confused words? Explore the most common comparisons:

• uracil vs. thymine
• thymidine vs. thymine

Example Sentences

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

Further, the team identified small sequences in the reversed code, repeated stretches of adenosine and thymine building blocks, known to be recognized by transcription factors, proteins that bind to DNA to initiate transcription.

From Science Daily • Mar. 6, 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

Against me was the awkward chemical fact that I had chosen the wrong tautomeric forms of guanine and thymine.

From "Double Helix" by James D. Watson