shut in vs insert

shut in is not a noun while insert is a noun.

Word	Noun	Adjective	Verb	Adverb
shut in	No	No	Yes	No
insert	Yes	No	Yes	No

As verbs, insert is a hyponym of shut in; that is, insert is a word with a more specific, narrower meaning than shut in:

shut in (noun)	insert (noun)
	(film) a still picture that is introduced and that interrupts the action of a film
	(broadcasting) a local announcement inserted into a network program
	an artifact that is inserted or is to be inserted
	a folded section placed between the leaves of another publication

shut in (verb)	insert (verb)
surround completely	place, fit, or thrust (something) into another thing
	insert casually
	put or introduce into something
	fit snugly into