To be up

  • Alxmrphi

    Senior Member
    UK English
    It means if someone loves themselves, or someone is "up someone elses arse" to be, sucking up to someone, it means to over flatter them.

    If someone is "up themselves" they are "up their own bum" which means, they think way too highly of themselves..
    So if someone says "Don't be up yourself!" it means 'don't think too highly of yourself' but with much more of an offensive slang feeling to it.

    Do you understand?