from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A single-ringed, crystalline organic base, C4H4N2, that forms uracil, cytosine, or thymine and is the parent compound of many drugs, including the barbiturates.
- n. Any of several organic compounds derived from or structurally related to pyrimidine, especially the nitrogen bases uracil, cytosine, and thymine.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A diazine in which the two nitrogen atoms are in the meta- positions; it is the basis of three of the bases found in DNA and RNA, thymine, uracil and cytosine
from The Century Dictionary and Cyclopedia
- n. An organic compound, composed of carbon, hydrogen, and nitrogen, so arranged that the carbon and nitrogen atoms form a ring or chain, as shown in the formula .
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. any of several basic compounds derived from pyrimidine
- n. a heterocyclic organic compound with a penetrating odor
Alteration of pyridine.(American Heritage® Dictionary of the English Language, Fourth Edition)