What does "thymine" mean?

A heterocyclic base, 5-methylpyrimidine-2,4(1H,3H)-dione; it pairs with adenine in DNA.

Thymine

/ˈθaɪmɪn/ noun

noun ·Rare ·Advanced level

Noun

1
A heterocyclic base, 5-methylpyrimidine-2,4(1H,3H)-dione; it pairs with adenine in DNA. countable, uncountable
"Then he found them, the substances that made up the four-letter alphabet in whose language all life is written — adenine and cytosine, guanine and thymine."
2
a base found in DNA (but not in RNA) and derived from pyrimidine; pairs with adenine wordnet

"DNA is composed of four nucleotides: adenine, thymine, cytosine and guanine."

From thymus + -ine. Thymine was first isolated in 1893 by Albrecht Kossel and Albert Neumann from calves' thymus glands, hence its name.