lecture vs preach

lecture is a noun but preach is not a noun.

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

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

Other hyponyms of lecture include prophesy.

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

lecture (verb)	preach (verb)
censure severely or angrily	speak, plead, or argue in favor of
deliver a lecture or talk	deliver a sermon