A polycyclic, somewhat carcinogenic hydrocarbon, structural parent of the highly carcinogenic 3 (or 20)-methylcholanthrene. ... (05 Mar 2000) ... 
Type: Term Pronunciation: kō-lan′thrēn Definitions: 1. A polycyclic, somewhat carcinogenic hydrocarbon, structural parent of the highly carcinogenic 3 (or 20)-methylcholanthrene.