uromelanin

ur·o·mel·a·nin

(yūr'ō-mel'ă-nin),
A black pigment occasionally found in the urine, possibly a decomposition product of urochrome.

uromelanin

(ū-rō-mĕl′ăn-ĭn) [″ + melas, black]
A black pigment occurring in urine resulting from the decomposition of urochrome.