fibroid tumor vs fibroma

fibroid tumor and fibroma both are nouns.

Word	Noun	Adjective	Verb	Adverb
fibroid tumor	Yes	No	No	No
fibroma	Yes	No	No	No

As nouns, fibroma is a hypernym of fibroid tumor; that is, fibroma is a word with a broader meaning than fibroid tumor:

fibroid tumor: benign tumor containing fibrous tissue (especially in the uterus)
fibroma: nonmalignant tumor of connective tissue

fibroid tumor (noun)	fibroma (noun)
benign tumor containing fibrous tissue (especially in the uterus)	nonmalignant tumor of connective tissue