Sabot

n. wooden shoe worn by European peasants, leather shoe with a thick wooden sole; one or several pieces of material that keeps an uncalibrated projectile centered inside a larger tube or launch container; dealing box for holding a few decks of playing cards

For the wooden shoe, see clog (shoe). For the sailing boat, see sabot (dinghy). A sabot (pronounced "sah-boh") refers to a device named for a shoe used in a firearm or cannon to fire a projectile or bullet that is smaller than the bore diameter. Since a strong seal is needed to trap propellant gasses behind the projectile, and keep the projectile centered in the barrel, something is needed to fill the gap between projectile and barrel, which is the role of the sabot. Firing a small size projectile wrapped in a sabot raises the muzzle velocity of the projectile. Made of some lightweight material (usually plastic in smallbore guns, and aluminum - and in earlier times; wood - in cannon), the sabot usually consists of several pieces held in place by the cartridge or a loose connection. When the projectile is fired, the sabot blocks the gas, and accelerates the projectile down the barrel. When the sabot reaches the end of the barrel, the shock of hitting still air pulls the parts of the sabot away from the projectile, allowing the projectile to continue in flight.
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Noun
1. a shoe carved from a single block of wood
(synonym) wooden shoe
(hypernym) shoe
2. footwear usually with wooden soles
(synonym) clog, geta, patten
(hypernym) footwear, footgear

n. clog, sabot; hoof

(n.)
A thick, circular disk of wood, to which the cartridge bag and projectile are attached, in fixed ammunition for cannon; also, a piece of soft metal attached to a projectile to take the groove of the rifling.
  

(n.)
A kind of wooden shoe worn by the peasantry in France, Belgium, Sweden, and some other European countries.