The curious phenomena by which men traveling in the back of large jostling vehicles (busses, vans, ect) tend to achieve spontaneous erection due initially to the jostling of the vehicle and then secondarily to the jostling of their own wood against their legs and/or pants. This erection can often be relieved only by extrication from the back seat.
Cody: Holy cow have I got a case of Back Seat Syndrome.
Matt: Boner city?
Cody: Worst ever. Switch me spots.
Matt: Boner city?
Cody: Worst ever. Switch me spots.
by Lord Azaldon April 18, 2013
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