WordNet sense 1 (a speech that is open to the public):

talk, public lecture

WordNet sense 2 (a lengthy rebuke):

speech

WordNet sense 3 (teaching by giving a discourse on some subject (typically to a class)):

lecturing

WordNet sense 4 (censure severely or angrily):

berate, chide, jaw, lambast, lambaste, rag, rebuke, remonstrate, reprimand, reproof, scold, trounce, reproof, call on the carpet, dress down, bawl out, call down, chew out, chew up, have words, take to task