This derives from one sourse that being the UK, Poo-whacker is somebody that is a shit-bag, coward, pussy, flapper or afraid of his/her own shadow.
"That blokes just got bitch slapped by a faggot and started crying, what a POO-WHACKER!!!!!"
by Poo-whcker hater!!! July 01, 2012
Can you define these popular missing words?