The Collaborative International Dictionary of English v.0.48:

Fisc \Fisc\ (f[i^]sk), n. [F. fisc, fr. L. fiscus basket, money
   basket, treasury; prob. akin to fascis bundle. See Fasces.]
   A public or state treasury. --Burke.
   [1913 Webster]

WordNet (r) 3.0 (2006):

F.I.S.C.
    n 1: a secret federal court created in 1978 by the Foreign
         Intelligence Surveillance Act; responsible for authorizing
         wiretaps and other forms of electronic surveillance and for
         authorizing searches of suspected spies and terrorists by
         the Department of Justice or United States intelligence
         agencies [syn: Foreign Intelligence Surveillance Court,
         F.I.S.C.]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

FISC, civil law. The treasury of a prince. The public treasury. Hence to
confiscate a thing, is to appropriate it to the fisc. Paillet, Droit Public,
21, n, says that fiscus, in the Roman law, signified the treasure of the
prince, and aerarium, the treasure of the state. But this distinction was
not observed in France. See Law 10, ff. De jure Fisci.