course credit vs attainment

course credit and attainment both are nouns.

Word	Noun	Adjective	Verb	Adverb
course credit	Yes	No	No	No
attainment	Yes	No	No	No

As nouns, attainment is a hypernym of course credit; that is, attainment is a word with a broader meaning than course credit:

course credit: recognition by a college or university that a course of studies has been successfully completed; typically measured in semester hours
attainment: the act of achieving an aim

course credit (noun)	attainment (noun)
recognition by a college or university that a course of studies has been successfully completed; typically measured in semester hours	the act of achieving an aim
	arrival at a new stage
	an ability that has been acquired by training