The Collaborative International Dictionary of English v.0.48:

Sardine \Sar"dine\ (? or ?; 277), n. [F. sardine (cf. Sp.
   sardina, sarda, It. sardina, sardella), L. sardina, sarda;
   cf. Gr. ?, ?; so called from the island of Sardinia, Gr. ?.]
   (Zool.)
   Any one of several small species of herring which are
   commonly preserved in olive oil for food, especially the
   pilchard, or European sardine (Clupea pilchardus). The
   California sardine (Clupea sagax) is similar. The American
   sardines of the Atlantic coast are mostly the young of the
   common herring and of the menhaden.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sardine \Sar"dine\ (? or ?; 277), n.
   See Sardius.
   [1913 Webster]

WordNet (r) 3.0 (2006):

sardine
    n 1: small fatty fish usually canned [syn: sardine,
         pilchard]
    2: any of various small edible herring or related food fishes
       frequently canned
    3: a deep orange-red variety of chalcedony [syn: sard,
       sardine, sardius]
    4: small fishes found in great schools along coasts of Europe;
       smaller and rounder than herring [syn: pilchard, sardine,
       Sardina pilchardus]