retirade

from The Collaborative International Dictionary of English v.0.48
Retirade \Ret`i*rade"\, n. [F.; cf. Sp. retirada retreat. See
   {Retire}.] (Fort.)
   A kind of retrenchment, as in the body of a bastion, which
   may be disputed inch by inch after the defenses are
   dismantled. It usually consists of two faces which make a
   reentering angle.
   [1913 Webster]
    

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