comprehend vs cotton on

comprehend and cotton on both are verbs.

Word	Noun	Adjective	Verb	Adverb
comprehend	No	No	Yes	No
cotton on	No	No	Yes	No

As verbs, cotton on is a hyponym of comprehend; that is, cotton on is a word with a more specific, narrower meaning than comprehend:

Other hyponyms of comprehend include figure, catch on, get it, get onto, get wise, latch on, tumble, twig, intuit, digest.

comprehend (verb)	cotton on (verb)
get the meaning of something	understand, usually after some initial difficulty
to become aware of through the senses
include in scope; include as part of something broader; have as one's sphere or territory