frown upon

frown upon (third-person singular simple present frowns upon, present participle frowning upon, simple past and past participle frowned upon)

1. (transitive) To disapprove of.

   Baiting fish is not illegal in this state, but strongly frowned upon.

   • 1962 September, Warren Smith, “The problems of coaching stock rostering and operation”, in Modern Railways, page 193:

     Regular passengers become familiar with their train and attempts to change its make-up or any other aspect of its working are more often than not frowned upon, even though the change is probably for the better.

• frown on
• frown at