top out vs attain

top out and attain both are verbs.

Word	Noun	Adjective	Verb	Adverb
top out	No	No	Yes	No
attain	No	No	Yes	No

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

Other hypernyms of top out include arrive at, gain, hit, make, reach.

top out (verb)	attain (verb)
to reach the highest point; attain maximum intensity, activity	reach a point in time, or a certain state or level
provide with a top or finish the top (of a structure)	reach a destination, either real or abstract
give up one's career just as one becomes very successful	find unexpectedly
	to gain with effort