learn vs lecture

learn is not a noun while lecture is a noun.

Word	Noun	Adjective	Verb	Adverb
learn	No	No	Yes	No
lecture	Yes	No	Yes	No

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

learn (noun)	lecture (noun)
	teaching by giving a discourse on some subject (typically to a class)
	a speech that is open to the public
	a lengthy rebuke

learn (verb)	lecture (verb)
gain knowledge or skills	censure severely or angrily
get to know or become aware of, usually accidentally	deliver a lecture or talk
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