1. A four sided die (d4) popular in role-playing games like Dungeons & Dragons.
"Ouch, Tom. Put your caltrop back into your dice bag..."
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.
J: caltrops, caltrops, CALTROP!
P: fuck guy, the staples are stuck in my foot!
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.