by Jake February 06, 2005
A metal ball that has 4 spikes arranged like the corners of a tetrahedron. Used for slowing calvalry. (The spikes stab into the horses hooves) I almost looks like a playing jack.
Sam layed the caltrops accross the roads and all the horses who ran through the road couldn't run anymore.
by Switch_lordoftheferrets February 15, 2004
A practical joke involving twisting a staple into a 3D triangluar shape so that when thrown on the ground, a pointy part will always stick up. Can be thrown into the back of peoples' shoes when they are leaning forward and distracted. Will produce a sharp pain in the inflicted and much anger towards the inflicter.
by Young Reezie January 29, 2008