benign tumour vs neoplasm

benign tumour and neoplasm both are nouns.

Word	Noun	Adjective	Verb	Adverb
benign tumour	Yes	No	No	No
neoplasm	Yes	No	No	No

As nouns, neoplasm is a hypernym of benign tumour; that is, neoplasm is a word with a broader meaning than benign tumour:

Other hypernyms of benign tumour include tumor, tumour.

benign tumour (noun)	neoplasm (noun)
a tumor that is not cancerous	an abnormal new mass of tissue that serves no purpose