flooring vs floorboard

flooring and floorboard both are nouns.

Word	Noun	Adjective	Verb	Adverb
flooring	Yes	No	No	No
floorboard	Yes	No	No	No

As nouns, floorboard is a hyponym of flooring; that is, floorboard is a word with a more specific, narrower meaning than flooring:

flooring: the inside lower horizontal surface (as of a room, hallway, tent, or other structure)
floorboard: the floor of an automobile

Other hyponyms of flooring include bell deck, dance floor, parquet, parquet floor, truck bed.

flooring (noun)	floorboard (noun)
the inside lower horizontal surface (as of a room, hallway, tent, or other structure)	a board in the floor
building material used in laying floors	the floor of an automobile