confine vs pen up

confine and pen up both are verbs.

Word	Noun	Adjective	Verb	Adverb
confine	No	No	Yes	No
pen up	No	No	Yes	No

As verbs, pen up is a hyponym of confine; that is, pen up is a word with a more specific, narrower meaning than confine:

confine: to close within bounds, or otherwise limit or deprive of free movement
pen up: confine in a fold, like sheep

confine (verb)	pen up (verb)
place limits on (extent or amount or access)	confine in a fold, like sheep
to close within bounds, or otherwise limit or deprive of free movement
prevent from leaving or from being removed
deprive of freedom; take into confinement
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