endeavour vs take pains

endeavour is a noun but take pains is not a noun.

Word	Noun	Adjective	Verb	Adverb
endeavour	Yes	No	Yes	No
take pains	No	No	Yes	No

As verbs, take pains is a hyponym of endeavour; that is, take pains is a word with a more specific, narrower meaning than endeavour:

Other hyponyms of endeavour include struggle, be at pains, buck.

endeavour (noun)	take pains (noun)
earnest and conscientious activity intended to do or accomplish something
a purposeful or industrious undertaking (especially one that requires effort or boldness)

endeavour (verb)	take pains (verb)
attempt by employing effort	try very hard to do something