French kiss vs buss

French kiss and buss both are nouns.

Word	Noun	Adjective	Verb	Adverb
French kiss	Yes	No	No	No
buss	Yes	No	Yes	No

As nouns, buss is a hypernym of French kiss; that is, buss is a word with a broader meaning than French kiss:

French kiss: an openmouthed kiss in which your tongue is inserted into the other's mouth
buss: the act of caressing with the lips (or an instance thereof)

Other hypernyms of French kiss include kiss, osculation.

French kiss (noun)	buss (noun)
an openmouthed kiss in which your tongue is inserted into the other's mouth	the act of caressing with the lips (or an instance thereof)

French kiss (verb)	buss (verb)
	touch with the lips or press the lips (against someone's mouth or other body part) as an expression of love, greeting, etc.