attainment vs success

attainment and success both are nouns.

Word	Noun	Adjective	Verb	Adverb
attainment	Yes	No	No	No
success	Yes	No	No	No

As nouns, success is a hyponym of attainment; that is, success is a word with a more specific, narrower meaning than attainment:

Other hyponyms of attainment include record, course credit, credit, accession, rise to power.

attainment (noun)	success (noun)
the act of achieving an aim	an attainment that is successful
arrival at a new stage	an event that accomplishes its intended purpose
an ability that has been acquired by training	a person with a record of successes
	a state of prosperity or fame