- Uracil (U) is one of four chemical bases that are part of RNA. The other three bases are adenine (A), cytosine (C), and guanine (G). In DNA, the base thymine (T) is used in place of uracil.
Definition from: Talking Glossary of Genetic Terms from the National Human Genome Research Institute
- A pyrimidine base (C4H4N2O2) that is one of the four bases coding genetic information in the polynucleotide chain of RNA.
Definition from: Merriam-Webster's Medical Dictionary by Merriam-Webster Inc.
See also Understanding Medical Terminology.