cast off vs slough

cast off is not a noun while slough is a noun.

Word	Noun	Adjective	Verb	Adverb
cast off	No	No	Yes	No
slough	Yes	No	Yes	No

As verbs, slough is a hyponym of cast off; that is, slough is a word with a more specific, narrower meaning than cast off:

Other hyponyms of cast off include exuviate, molt, moult, shed, abscise, exfoliate, autotomise, autotomize.

cast off (noun)	slough (noun)
	any outer covering that can be shed or cast off (such as the cast-off skin of a snake)
	necrotic tissue; a mortified or gangrenous part or mass
	a stagnant swamp (especially as part of a bayou)
	a hollow filled with mud

cast off (verb)	slough (verb)
to remove	cast off hair, skin, horn, or feathers
make the last row of stitches when knitting