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3.
A man who enjoys watching younger males shower. Most Willy Watchers are employed in public schools as P.E. teachers.
That Mr. Andersen always seems to be in the changing rooms after P.E. He is fucking creepy, that Willy Watcher.
by geezerdk January 02, 2012
 
1.
A man that stands next to you in the gents toilets and spends all the time eyeing up yer wood
You:I was in the toilets and Tom came in and stared at my penis.
Friend:Didn't you know he waas a Willy watcher
by Geordie Boy October 14, 2003
 
2.
A woman (or cruising gay man) who checks out trouser bulges to estimate the size of the owner's penis.
Hilda loves big dick; she's a willy-watcher 24/7.
by Edna Sweetlove July 30, 2010