What is the meaning of Backside?

The back side of anything, the part opposite its front, particularly:

  1. The back side of an estate: the backyard and outbuildings behind a main house, especially an outhouse.

    The back side of an estate: the backyard and outbuildings behind a main house, especially an outhouse.

    A person's buttocks.

    The back side of a page: a verso.

    The reverse or opposite of anything.

    Used other than figuratively or idiomatically: see back, side.

    Approaching an obstacle backward

    Used other than figuratively or idiomatically: see back, side.

    backside

    Source: wiktionary.org