The vehicle of retired gay pornstar Billy Herrington. It is composed of a naked body builder whom is being rode by Harrington, also naked. It can work as a segway, a motorcycle, etc.

Term invented by Michael Swaim of Cracked.com
-southern car dealer accent- Are you looking for a brand new or used dude-car? Then come on down to Harrington's, where we just got our brand new shipment of 2011 b-b-b-b-b-b-bonercycles! On a tight budget? Check out our wide range of gently used O rings. And we got all the added features! High beams, low beams, anti-lock balls! MMmm! Check out the paintjob on that! So come on down to Harrington's, where we don't jerk you around! Unless that's your thing, in which case... Mmmmm.... Yeah.... Woooo! THIS COULD BE YOU!
by Merc29 December 10, 2010
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The exact definition of bonercycle is unknown, due to debate between the following two definitions:

Definition 1:
An irresistable penis that females want to "ride". Similar to a motorcycle.

Definition 2:
A cycle with steps such as: limp, half-mast, and hard-on. Similar to a life cycle.
"I really wanna ride that hippie's bonercycle"

"My bonercycle is always at stage one, limp :("
by GarnetOakley October 22, 2007
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A moto so sweet it gives you a boner.
Ooooh! Check out that sweet Ducati -- BONERCYCLE!
by kookymiyuki April 21, 2011
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