having a bat

To engage in the act of masturbation. Can also be known as 'whacking it'

person 1: "ey why u watching that porno for"
person 2: " im thinking of having a bat.

by Markwick October 06, 2009

have a bat

To wank

I think it's the right time to have a bat!

by thewizardandhisfellows September 16, 2013

Have bats in ones belfry

To be crazy or eccentric

She seems to have bats in her belfry.

by Light Joker March 14, 2004