Source : Webster's Revised Unabridged Dictionary (1913)

Batoidei \Ba*toi"de*i\, n. pl. [NL., fr. Gr. ba`tos a kind of
   ray + -oid.] (Zo["o]l.)
   The division of fishes which includes the rays and skates.

Source : WordNet®

Batoidei
     n : fish with dorsoventrally flattened bodies; includes: rays;
         skates; guitarfishes; sawfishes [syn: {Rajiformes}, {order
         Rajiformes}, {order Batoidei}]