Someone who washes their penis on the urinal flush stream. To do this, they normally thrust their pelvis (and thus penis) deep into the urinal, until the penis touches the stream. They will then flush the urinal, often repeatedly, until they deem their penis to be clean. Paper towel is then used to dry the penis.

One variant is to just use a paper towel (available in most public washrooms) run the paper towel under the urinal stream, and then wash the penis manually with the paper towel.
That guy is a "wanker washer". I saw him washing his wanker in the urinal yesterday.
by Dave March 4, 2003
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