(from Latin) A fun, but more polite and generally, highly acceptable, way of saying brain fart or cerebral flatulence.
David 1: "Oops, sorry, David I MEANT to say I'll hold the fence panel and you hammer the nail in (not screw it in). I think I just had a brain fart."
David 2 (seeming a bit shocked): "A what???"
David 1: "Cerebral flatulence."
David 2: (looking a little confused): "Eh?"
David 1: "A "lapsus mentis"."
David 2: (still looking a little puzzled but just getting it): "Oh!"
David 2 (seeming a bit shocked): "A what???"
David 1: "Cerebral flatulence."
David 2: (looking a little confused): "Eh?"
David 1: "A "lapsus mentis"."
David 2: (still looking a little puzzled but just getting it): "Oh!"
by LangFill May 18, 2017