be not on
(redirected from being not on)be not on
To be inappropriate and/or unfair, as of one's behavior. I'm sorry, but it's just not on to spread gossip about someone.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
it's not on
it's impractical or unacceptable. informalFarlex Partner Idioms Dictionary © Farlex 2017
(just) not ˈon
(informal) not a good or an acceptable way to behave: He told her that using his bike without asking just wasn’t on. ♢ It’s not on — you should know better.Farlex Partner Idioms Dictionary © Farlex 2017