[1] : The Collaborative International Dictionary of English v.0.48

sprat \sprat\ spra^t, n. oe. sprot, sprotte, d. sprot; akin
   to g. sprotte. zool.
   a a small european herring clupea sprattus closely
       allied to the common herring and the pilchard; -- called
       also garvie. the name is also applied to small herring
       of different kinds.
   b a california surf-fish rhacochilus toxotes; -- called
       also alfione, and perch.
       1913 webster

   sprat borer zool., the red-throated diver; -- so called
      from its fondness for sprats. see diver.

   sprat loon. zool.
   a the young of the great northern diver. prov. eng.
   b the red-throated diver. see diver.

   sprat mew zool., the kittiwake gull.
      1913 webster
see also:
clupea sprattus garvie rhacochilus toxotes alfione perch sprat borer 
diver sprat loon sprat mew 

[2] : WordNet (r) 2.0

sprat
     n 1: small fatty european fish; usually smoked or canned like
          sardines syn: brisling
     2: small herring processed like a sardine syn: brisling, clupea
        sprattus
see also:
brisling clupea sprattus 

Sprat >> S Words
Sprat, definition of term: Sprat
sprat_pag1.html