bile duct vs common bile duct

bile duct and common bile duct both are nouns.

Word	Noun	Adjective	Verb	Adverb
bile duct	Yes	No	No	No
common bile duct	Yes	No	No	No

As nouns, bile duct and common bile duct are synonyms defined as:

bile duct and common bile duct: a duct formed by the hepatic and cystic ducts; opens into the duodenum

bile duct (noun)	common bile duct (noun)
a duct formed by the hepatic and cystic ducts; opens into the duodenum	a duct formed by the hepatic and cystic ducts; opens into the duodenum