com ‧ men ‧ ta ‧ tor AC /ˈkɒmənteɪtə $ ˈkɑːmənteɪtər/ BrE AmE noun [countable]
[ Date: 1300-1400 ; Language: Latin ; Origin: commentari 'to comment' , from comminisci ; ⇨ ↑ comment 1 ]
1 . someone who knows a lot about a particular subject, and who writes about it or discusses it on the television or radio:
political commentators
2 . someone on television or radio who describes an event as it is happening:
a sports commentator