lusus naturae vs monster

lusus naturae and monster both are nouns.

Word	Noun	Adjective	Verb	Adverb
lusus naturae	Yes	No	No	No
monster	Yes	No	No	No

As nouns, lusus naturae and monster are synonyms defined as:

lusus naturae and monster: a person or animal that is markedly unusual or deformed

Other synonyms of lusus naturae include freak, monstrosity.

lusus naturae (noun)	monster (noun)
a person or animal that is markedly unusual or deformed	(medicine) a grossly malformed and usually nonviable fetus
	a cruel wicked and inhuman person
	a person or animal that is markedly unusual or deformed
	an imaginary creature usually having various human and animal parts
	someone that is abnormally large and powerful