sit out vs brook

sit out is not a noun while brook is a noun.

Word	Noun	Adjective	Verb	Adverb
sit out	No	No	Yes	No
brook	Yes	No	Yes	No

As verbs, brook is a hypernym of sit out; that is, brook is a word with a broader meaning than sit out:

Other hypernyms of sit out include abide, bear, digest, endure, put up, stand, stick out, stomach, suffer, support, tolerate.

sit out (noun)	brook (noun)
	a natural stream of water smaller than a river (and often a tributary of a river)

sit out (verb)	brook (verb)
endure to the end	put up with something or somebody unpleasant
not participate in (an activity, such as a dance or a sports event)