A fork of Rural Dictionary
If someone does something that is extremely unfair, or says something thats offensive or hurtful.
Betsy: He called me a whore! Lisa : That's bang out of order...
British slang, it means something thats very offensive or extremely unfair.
Kid: You're a liar, Harry! Harry: *Stomps upstairs and Ron follows him.* Ron: That's bang out of order!