The Collaborative International Dictionary of English v.0.48:

Enclave \En*clave"\, n. [F., fr. L. in + clavus a nail.]
   A tract of land or a territory inclosed within another
   territory of which it is independent. See Exclave. [Recent]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Enclave \En*clave"\, v. t. [Cf. F. enclaver.]
   To inclose within an alien territory. [Recent]
   [1913 Webster]

WordNet (r) 3.0 (2006):

enclave
    n 1: an enclosed territory that is culturally distinct from the
         foreign territory that surrounds it

Moby Thesaurus II by Grady Ward, 1.0:

39 Moby Thesaurus words for "enclave":
   arena, block, cincture, clos, close, confine, container, coop,
   court, courtyard, croft, curtilage, delimited field, enclosure,
   field, fold, forty, ground, kraal, list, lot, pale, paling,
   parcel of land, park, patch, pen, plat, plot, plot of ground, quad,
   quadrangle, real estate, section, square, theater, toft, tract,
   yard