The Collaborative International Dictionary of English v.0.48:

Calamari \Cal"a*mar`i\ (k[a^]l`[.a]*m[aum]r"[-e]), n. [It.
   calamari, fr. LL. calamarium inkstand, fr. L. calamus a reed
   pen: cf. F. calmar, calemar, pen case, calamar.] (Cookery)
   Squid, used as a food; -- from the Italian word. See Squid.
   [PJC]

WordNet (r) 3.0 (2006):

calamari
    n 1: (Italian cuisine) squid prepared as food [syn: squid,
         calamari, calamary]