What is "sprag"

Sprag \Sprag\, v. t. [imp. & p. p. Spragged (spr[a^]gd); p. pr. & vb. n. Spragging (-g[i^]ng).]

1. To check the motion of, as a carriage on a steep grade, by putting a sprag between the spokes of the wheel.
   --R. S. Poole.

2. To prop or sustain with a sprag.

Sprag \Sprag\, a. See Sprack, a.
--Shak.

Sprag \Sprag\ (spr[a^]g), n. [Cf. Icel. spraka a small flounder.] (Zo["o]l.) A young salmon. [Prov. Eng.]

Sprag \Sprag\, n. [See Spray a branch.] A billet of wood; a piece of timber used as a prop.

"prop in a mine," 1841, of unknown origin. Transferred by 1878 to wood blocks, etc., used to brake motor vehicles. As a verb, from 1841. Related: Spragged; spragging.

Etymology 1

1. (alternative form of sprack English) Etymology 2

   n. A billet of wood; a piece of timber, a similar solid object or constructed unit used as a prop. v

2. 1 (context transitive English) To check the motion of, as a carriage on a steep slope, by putting a sprag between the spokes of the wheel. 2 (context transitive English) To prop or sustain with a sprag. Etymology 3

   n. A young salmon.

1. n. a chock or bar wedged under a wheel or between the spokes to prevent a vehicle from rolling down an incline

2. a wooden prop used to support the roof of a mine [syn: pitprop]