尿にょう素そ回かい路ろにょうそかいろMeanings1nounurea cycleBiochemical term for the metabolic pathway that converts ammonia into urea. Also called オルニチン回路 (ornithine cycle).See also: オルニチン回路尿にょう素そ回かい路ろは肝かん臓ぞうでアンモニアを尿にょう素そ