freeload vs grub

freeload is not a noun while grub is a noun.

Word	Noun	Adjective	Verb	Adverb
freeload	No	No	Yes	No
grub	Yes	No	Yes	No

As verbs, grub is a hypernym of freeload; that is, grub is a word with a broader meaning than freeload:

Other hypernyms of freeload include bum, cadge, mooch, sponge.

freeload (noun)	grub (noun)
	a soft thick wormlike larva of certain beetles and other insects
	informal terms for a meal

freeload (verb)	grub (verb)
live off somebody's generosity	search about busily
	ask for and get free; be a parasite