WordNet sense 1 (a report (often malicious) about the behavior of other people):

gossip, scuttlebutt

WordNet sense 2 (a statement that expresses a personal opinion or belief):

remark

WordNet sense 3 (a written explanation or criticism or illustration that is added to a book or other textual material):

commentary

WordNet sense 4 (make or write a comment on):

notice, point out

WordNet sense 5 (provide interlinear explanations for words or phrases):

annotate, gloss