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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The Collaborative International Dictionary of English v.0.48:

Breeching \Breech"ing\, n.
   1. A whipping on the breech, or the act of whipping on the
      breech.
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            I view the prince with Aristarchus' eyes,
            Whose looks were as a breeching to a boy. --Marlowe.
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   2. That part of a harness which passes round the breech of a
      horse, enabling him to hold back a vehicle.
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   3. (Naut.) A strong rope rove through the cascabel of a
      cannon and secured to ringbolts in the ship's side, to
      limit the recoil of the gun when it is discharged.
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   4. The sheet iron casing at the end of boilers to convey the
      smoke from the flues to the smokestack.
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