roundhead vs mortal

roundhead and mortal both are nouns.

Word	Noun	Adjective	Verb	Adverb
roundhead	Yes	No	No	No
mortal	Yes	Yes	No	No

As nouns, mortal is a hypernym of roundhead; that is, mortal is a word with a broader meaning than roundhead:

roundhead: a brachycephalic person
mortal: a human being; person, singular, assertive existential pronoun; pronoun, person, singular; quantifier: assertive existential

Other hypernyms of roundhead include individual, person, somebody, someone, soul.

roundhead (noun)	mortal (noun)
a brachycephalic person	a human being; person, singular, assertive existential pronoun; pronoun, person, singular; quantifier: assertive existential

roundhead (adjective)	mortal (adjective)
	subject to death
	unrelenting and deadly
	involving loss of divine grace or spiritual death
	causing or capable of causing death