A pyrimidine base, C5H6N2O2, that is an essential constituent of DNA. (noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "thymine" in a sentence
"The two others, thymine and cytosine, showed a simpler composition; experiments of breakdown and synthesis led to the result that in thymine there must be a grouping of the carbon and nitrogen atoms corresponding to the following scheme:"
"It is evident from the formulae that in thymine and cytosine a ring-like system of carbon and nitrogen atoms must be assumed."
"The UVA1 induced a type of lesion called thymine dimers on the deeper basal layers of the skin."