learn vs catch up

learn and catch up both are verbs.

Word	Noun	Adjective	Verb	Adverb
learn	No	No	Yes	No
catch up	No	No	Yes	No

As verbs, catch up is a hyponym of learn; that is, catch up is a word with a more specific, narrower meaning than learn:

Other hyponyms of learn include relearn, absorb, assimilate, ingest, take in, hit the books, study.

learn (verb)	catch up (verb)
gain knowledge or skills	learn belatedly; find out about something after it happened
get to know or become aware of, usually accidentally	reach the point where one should be after a delay
be a student of a certain subject
commit to memory; learn by heart
impart skills or knowledge to
find out, learn, or determine with certainty, usually by making an inquiry or other effort