Sheetrock vs gypsum board

Sheetrock and gypsum board both are nouns.

Word	Noun	Adjective	Verb	Adverb
Sheetrock	Yes	No	No	No
gypsum board	Yes	No	No	No

As nouns, gypsum board is a hypernym of Sheetrock; that is, gypsum board is a word with a broader meaning than Sheetrock:

Sheetrock: a kind of plasterboard
gypsum board: wallboard with a gypsum plaster core bonded to layers of paper or fiberboard; used instead of plaster or wallboard to make interior walls

Other hypernyms of Sheetrock include plasterboard.

Sheetrock (noun)	gypsum board (noun)
a kind of plasterboard	wallboard with a gypsum plaster core bonded to layers of paper or fiberboard; used instead of plaster or wallboard to make interior walls