witch broom vs tussock

witch broom and tussock both are nouns.

Word	Noun	Adjective	Verb	Adverb
witch broom	Yes	No	No	No
tussock	Yes	No	No	No

As nouns, tussock is a hypernym of witch broom; that is, tussock is a word with a broader meaning than witch broom:

witch broom: an abnormal tufted growth of small branches on a tree or shrub caused by fungi or insects or other physiological disturbance
tussock: a bunch of hair or feathers or growing grass

Other hypernyms of witch broom include tuft.

witch broom (noun)	tussock (noun)
an abnormal tufted growth of small branches on a tree or shrub caused by fungi or insects or other physiological disturbance	a bunch of hair or feathers or growing grass