deterrent vs difficulty

deterrent and difficulty both are nouns.

Word	Noun	Adjective	Verb	Adverb
deterrent	Yes	Yes	No	No
difficulty	Yes	No	No	No

As nouns, difficulty is a hypernym of deterrent; that is, difficulty is a word with a broader meaning than deterrent:

deterrent: something immaterial that interferes with or delays action or progress
difficulty: the quality of being almost beyond one's ability to deal with and requiring a great effort to achieve a positive result

Other hypernyms of deterrent include difficultness.

deterrent (noun)	difficulty (noun)
something immaterial that interferes with or delays action or progress	an effort that is inconvenient
	the quality of being almost beyond one's ability to deal with and requiring a great effort to achieve a positive result

deterrent (adjective)	difficulty (adjective)
tending to deter