Dear oh dear, I appear to be the first
British noder to stoop so low as to add a
writeup here. Still,
I know no shame, so I shall take great delight in informing the
global Everything community that "
willy" is no less than
playground slang for a
penis. Of course in every school there will be at least one poor
pupil whose given name is "William", which inevitably results in the poor kid spending at least a few
weeks being surrounded by 7-year olds yelling "<.i>Ha ha, you're name is Willy! What's your surname, then: Bum?".
As well as being the most common word describing the male genitals for those at primary school, it's also occasionally used by adults for when "penis" sounds a bit too clinical yet the harder (no pun intended) words such as dick, cock etc sound a bit too out of place. Not common amongst grown-ups though.