A morphologic variant of extrahepatic bile duct adenocarcinoma characterized by the presence of malignant glandular epithelium composed of clear cells. The disease is extrahepatic bile duct clear cell adenocarcinoma (MONDO_0004081). Also known as: bile duct clear cell adenocarcinoma, bile duct clear cell carcinoma, clear cell adenocarcinoma of bile duct, clear cell adenocarcinoma of the bile duct, clear cell bile duct adenocarcinoma.