Pneumatic pile

Pile Pile, n. [AS. p[=i]l arrow, stake, L. pilum javelin; but cf. also L. pila pillar.] 1. A large stake, or piece of timber, pointed and driven into the earth, as at the bottom of a river, or in a harbor where the ground is soft, for the support of a building, a pier, or other superstructure, or to form a cofferdam, etc. [1913 Webster]

Note: Tubular iron piles are now much used. [1913 Webster]

2. [Cf. F. pile.] (Her.) One of the ordinaries or subordinaries having the form of a wedge, usually placed palewise, with the broadest end uppermost. [1913 Webster]

{Pile bridge}, a bridge of which the roadway is supported on piles.

{Pile cap}, a beam resting upon and connecting the heads of piles.

{Pile driver}, or {Pile engine}, an apparatus for driving down piles, consisting usually of a high frame, with suitable appliances for raising to a height (by animal or steam power, the explosion of gunpowder, etc.) a heavy mass of iron, which falls upon the pile.

{Pile dwelling}. See {Lake dwelling}, under {Lake}.

{Pile plank} (Hydraul. Eng.), a thick plank used as a pile in sheet piling. See {Sheet piling}, under {Piling}.

{Pneumatic pile}. See under {Pneumatic}.

{Screw pile}, one with a screw at the lower end, and sunk by rotation aided by pressure. [1913 Webster]