Disposable diaper disposed of inappropriately. Tightly wrapped to form a ball shape, these are often left behind in parking lots or walkways through which strollers pass. Sometimes these are thrown from a moving vehicle, though probably not directly from a stroller.

See: pram grenade.
Careful, you don't want to step on a stroller bomb. This parking lot is full of them.
by BillVo November 18, 2012
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