culminate vs achieve

culminate and achieve both are verbs.

Word	Noun	Adjective	Verb	Adverb
culminate	No	No	Yes	No
achieve	No	No	Yes	No

As verbs, achieve is a hypernym of culminate; that is, achieve is a word with a broader meaning than culminate:

Other hypernyms of culminate include accomplish, attain, reach.

culminate (verb)	achieve (verb)
end, especially to reach a final or climactic stage	to gain with effort
rise to, or form, a summit
bring to a head or to the highest point
reach the highest altitude or the meridian, of a celestial body
reach the highest or most decisive point