From The Collaborative International Dictionary of English v.0.48:
Breech \Breech\ (br[=e]ch or br[i^]ch; 277), n. [See
Breeches.]
1. The lower part of the body behind; the buttocks.
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2. Breeches. [Obs.] --Shak.
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3. The hinder part of anything; esp., the part of a cannon,
or other firearm, behind the chamber.
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4. (Naut.) The external angle of knee timber, the inside of
which is called the throat.
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From The Collaborative International Dictionary of English v.0.48:
Breech \Breech\, v. t. [imp. & p. p. Breeched; p. pr. & vb. n.
Breeching.]
1. To put into, or clothe with, breeches.
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A great man . . . anxious to know whether the
blacksmith's youngest boy was breeched. --Macaulay.
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2. To cover as with breeches. [Poetic]
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Their daggers unmannerly breeched with gore. --Shak.
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3. To fit or furnish with a breech; as, to breech a gun.
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4. To whip on the breech. [Obs.]
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Had not a courteous serving man conveyed me away,
whilst he went to fetch whips, I think, in my
conscience, he would have breeched me. --Old Play.
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5. To fasten with breeching.
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