coast vs slope

coast and slope both are nouns.

Word	Noun	Adjective	Verb	Adverb
coast	Yes	No	Yes	No
slope	Yes	No	Yes	No

As nouns, slope is a hypernym of coast; that is, slope is a word with a broader meaning than coast:

Other hypernyms of coast include incline, side.

coast (noun)	slope (noun)
the act of moving smoothly along a surface while remaining in contact with it	the property possessed by a line or surface that departs from the horizontal
the area within view	an elevated geological formation
the shore of a sea or ocean
a slope down which sleds may coast

coast (verb)	slope (verb)
move effortlessly; by force of gravity	be at an angle