noun. Any of various compounds consisting of a nucleoside combined with a phosphate group and forming the basic constituent of DNA and RNA.

noun. a phosphate ester of a nucleoside; one of the monomeric components of DNA or RNA.

noun. the monomer comprising DNA or RNA biopolymer molecules. Each nucleotide consists of a nitrogenous heterocyclic base (or nucleobase), which can be either a double-ringed purine or a single-ringed pyrimidine; a five-carbon pentose sugar (deoxyribose in DNA or ribose in RNA); and a phosphate group.

noun. a phosphoric ester of a nucleoside; the basic structural unit of nucleic acids (DNA or RNA)

"Pharmasset's lead hepatitis C drug, PSI-7977, is known as a nucleotide polymerase inhibitor and is designed to combat hepatitis C infection inside liver cells."