impound vs restrain

impound and restrain both are verbs.

Word	Noun	Adjective	Verb	Adverb
impound	No	No	Yes	No
restrain	No	No	Yes	No

As verbs, restrain is a hypernym of impound; that is, restrain is a word with a broader meaning than impound:

impound: place or shut up in a pound
restrain: to close within bounds, or otherwise limit or deprive of free movement

Other hypernyms of impound include confine, constrain, hold.

impound (verb)	restrain (verb)
place or shut up in a pound	prevent the action or expression of
take temporary possession of as a security, by legal authority	to close within bounds, or otherwise limit or deprive of free movement
	restrict (someone or something) so as to make free movement difficult
	prevent (someone or something) from doing something