cotton flannel vs fabric

cotton flannel and fabric both are nouns.

Word	Noun	Adjective	Verb	Adverb
cotton flannel	Yes	No	No	No
fabric	Yes	No	No	No

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

cotton flannel: a stout cotton fabric with nap on only one side
fabric: artifact made by weaving or felting or knitting or crocheting natural or synthetic fibers

Other hypernyms of cotton flannel include cloth, material, textile.

cotton flannel (noun)	fabric (noun)
a stout cotton fabric with nap on only one side	artifact made by weaving or felting or knitting or crocheting natural or synthetic fibers
	the underlying structure