teaching vs lecture

teaching and lecture both are nouns.

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

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

teaching: the profession of a teacher
lecture: teaching by giving a discourse on some subject (typically to a class)

teaching (noun)	lecture (noun)
the profession of a teacher	teaching by giving a discourse on some subject (typically to a class)
the activities of educating or instructing; activities that impart knowledge or skill	a speech that is open to the public
a doctrine that is taught	a lengthy rebuke

teaching (verb)	lecture (verb)
	censure severely or angrily
	deliver a lecture or talk