What is "gate valva"

Gate \Gate\ (g[=a]t), n. [OE. [yogh]et, [yogh]eat, giat, gate, door, AS. geat, gat, gate, door; akin to OS., D., & Icel. gat opening, hole, and perh. to E. gate a way, gait, and get, v. Cf. Gate a way, 3d Get.]

1. A large door or passageway in the wall of a city, of an inclosed field or place, or of a grand edifice, etc.; also, the movable structure of timber, metal, etc., by which the passage can be closed.

2. An opening for passage in any inclosing wall, fence, or barrier; or the suspended framework which closes or opens a passage. Also, figuratively, a means or way of entrance or of exit.

   Knowest thou the way to Dover? Both stile and gate, horse way and footpath.
   --Shak.

   Opening a gate for a long war.
   --Knolles.

3. A door, valve, or other device, for stopping the passage of water through a dam, lock, pipe, etc.

4. (Script.) The places which command the entrances or access; hence, place of vantage; power; might.

   The gates of hell shall not prevail against it.
   --Matt. xvi. 18.

5. In a lock tumbler, the opening for the stump of the bolt to pass through or into.

6. (Founding)

   1. The channel or opening through which metal is poured into the mold; the ingate.

   2. The waste piece of metal cast in the opening; a sprue or sullage piece. [Written also geat and git.]

      Gate chamber, a recess in the side wall of a canal lock, which receives the opened gate.

      Gate channel. See Gate, 5.

      Gate hook, the hook-formed piece of a gate hinge.

      Gate money, entrance money for admission to an inclosure.

      Gate tender, one in charge of a gate, as at a railroad crossing.

      Gate valva, a stop valve for a pipe, having a sliding gate which affords a straight passageway when open.

      Gate vein (Anat.), the portal vein.

      To break gates (Eng. Univ.), to enter a college inclosure after the hour to which a student has been restricted.

      To stand in the gate or To stand in the gates, to occupy places or advantage, power, or defense.