snake oil vs deceit

snake oil and deceit both are nouns.

Word	Noun	Adjective	Verb	Adverb
snake oil	Yes	No	No	No
deceit	Yes	No	No	No

As nouns, deceit is a hypernym of snake oil; that is, deceit is a word with a broader meaning than snake oil:

Other hypernyms of snake oil include deception, misrepresentation.

snake oil (noun)	deceit (noun)
communication (written or spoken) intended to deceive	the act of deceiving
(medicine) any of various liquids sold as medicine (as by a travelling medicine show) but medically worthless	the quality of being fraudulent
	a misleading falsehood