'citrulline' definitions:

Definition of 'citrulline'

(from WordNet)
noun
An amino acid that does not occur in proteins but is an intermediate in the conversion of ornithine to arginine

Definition of 'citrulline'

From: GCIDE
  • citrulline \citrulline\ n. an amino acid that is an intermediate in the conversion of ornithine to arginine. [WordNet 1.5]