letch vs pervert

letch and pervert both are nouns.

Word	Noun	Adjective	Verb	Adverb
letch	Yes	No	No	No
pervert	Yes	No	Yes	No

As nouns, pervert is a hypernym of letch; that is, pervert is a word with a broader meaning than letch:

letch: man with strong sexual desires
pervert: a person whose behavior deviates from what is acceptable especially in sexual behavior

Other hypernyms of letch include degenerate, deviant, deviate, perv, perve.

letch (noun)	pervert (noun)
man with strong sexual desires	a person whose behavior deviates from what is acceptable especially in sexual behavior

letch (verb)	pervert (verb)
	change the inherent purpose or function of something
	practice sophistry; change the meaning of or be vague about in order to mislead or deceive
	corrupt morally or by intemperance or sensuality