opaska

1. remark; comment
   Njegova opaska o mojoj frizuri me je naljutila. — His remark about my haircut annoyed me.
   Imaš li neku opasku na moj predlog? — Do you have any comments on my proposal?
2. (in a text) note; annotation
   Na margini je dopisao nekoliko opaski olovkom. — He pencilled a few notes in the margin.

Common pattern: opaska na račun + gen., a remark aimed at someone.