the done thing

the done thing

A given behavior that is acceptable, appropriate, or correct in a particular social situation. Often used in the negative to convey the opposite. Calling on a friend when they are sick is simply the done thing. You should know better than to wear a skirt like that to a formal dinner—it is simply not the done thing! I'm so glad smoking indoors is not the done thing anymore!
See also: done, thing
Farlex Dictionary of Idioms.

the done ˈthing

(British English) the socially correct way to behave: Smoking while somebody else is eating is not the done thing. It’s the done thing to dress for dinner in this hotel.
See also: done, thing
Farlex Partner Idioms Dictionary
See also:
  • bother about
  • bother about (someone or something)
  • bother with
  • bother with (someone or something)
  • count for
  • count for (something)
  • break the bank
  • break the bank, to
  • be (not) as black as (someone or something) is painted
  • be (not) (one's) style
References in periodicals archive
and w f That's not the done thing for a jockey riding at eight stone.