The Collaborative International Dictionary of English v.0.48:

Inbreed \In*breed"\, v. t. [imp. & p. p. Inbred; p. pr. & vb.
   n. Inbreeding.] [Cf. Imbreed.]
   [1913 Webster]
   1. To produce or generate within. --Bp. Reynolds.
      [1913 Webster]

            To inbreed and cherish . . . the seeds of virtue.
                                                  --Milton.
      [1913 Webster]

   2. To breed in and in. See under Breed, v. i.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

18 Moby Thesaurus words for "inbreed":
   beget, breed, breed true, copulate, crossbreed, engender, father,
   generate, get, make love, mother, multiply, outbreed, procreate,
   proliferate, propagate, reproduce in kind, sire