suck in vs hollow

suck in is not a noun while hollow is a noun.

Word	Noun	Adjective	Verb	Adverb
suck in	No	No	Yes	No
hollow	Yes	Yes	Yes	No

As verbs, hollow is a hypernym of suck in; that is, hollow is a word with a broader meaning than suck in:

Other hypernyms of suck in include core out, hollow out.

suck in (noun)	hollow (noun)
	a depression hollowed out of solid matter
	a small valley between mountains
	a cavity or space in something

suck in (adjective)	hollow (adjective)
	not solid; having a space or gap or cavity
	lacking in substance or character
	devoid of significance or force
	as if echoing in a hollow space

suck in (verb)	hollow (verb)
take up as if with a sponge	remove the interior of
draw in as if by suction	remove the inner part or the core of
attract by using an inexorable force, inducement, etc.