1.nounA machine for forcing a pile, a long beam, into the ground as part of the construction of a foundation; usually by raising a weight and then dropping it on the beam.
2.nounA person who hits or attacks forcefully or powerfully.
"She sure is a pile driver"
3.nounA move in which the wrestler applies a front waist lock, then drives the opponent's head into the mat by falling to his knees or backside.