piece of cloth vs fabric

piece of cloth and fabric both are nouns.

Word	Noun	Adjective	Verb	Adverb
piece of cloth	Yes	No	No	No
fabric	Yes	No	No	No

As nouns, fabric is a hypernym of piece of cloth; that is, fabric is a word with a broader meaning than piece of cloth:

piece of cloth: a separate part consisting of fabric
fabric: artifact made by weaving or felting or knitting or crocheting natural or synthetic fibers

Other hypernyms of piece of cloth include cloth, material, textile, piece.

piece of cloth (noun)	fabric (noun)
a separate part consisting of fabric	artifact made by weaving or felting or knitting or crocheting natural or synthetic fibers
	the underlying structure