benign tumour vs nonmalignant neoplasm

benign tumour and nonmalignant neoplasm both are nouns.

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

As nouns, benign tumour and nonmalignant neoplasm are synonyms defined as:

Other synonyms of benign tumour include benign tumor, nonmalignant tumor, nonmalignant tumour.

benign tumour (noun)	nonmalignant neoplasm (noun)
a tumor that is not cancerous	a tumor that is not cancerous