1 definition by aprilstarchild

Someone who is riding their bicycle in dark/low visibility conditions, without a headlight or taillight. So-called because they are invisible, like a ninja.

The webcomic Yehuda Moon had a comic illustrating a bike ninja on April 14th.
I wasn't expecting to be out this late, so I didn't have my lights with me, and I was a bike ninja for the ride home.

When I crossed the intersection, I was almost hit by a bike ninja! Dude needs to get some lights and look where he's going.

by aprilstarchild May 23, 2008
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