The chemical reactions and pathways resulting in the breakdown of ornithine, an amino acid only rarely found in proteins, but which is important in living organisms as an intermediate in the reactions of the urea cycle and in arginine biosynthesis. [ https://www.worldcat.org/search?q=bn%3A0192801023 GOC:jl ]
Synonyms: ornithine catabolism ornithine degradation ornithine breakdown