The Collaborative International Dictionary of English v.0.48:

Malacopterygii \Mal`a*cop`te*ryg"i*i\, prop. n. pl. [NL., fr.
   Gr. malako`s soft + pte`ryx wing, fin, fr. ptero`n feather.]
   (Zool.)
   An order of fishes in which the fin rays, except the anterior
   ray of the pectoral and dorsal fins, are closely jointed, and
   not spiny. It includes the carp, pike, salmon, shad, etc.
   Called also Malacopteri.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Malacopterygii
    n 1: an extensive group of teleost fishes having fins supported
         by flexible cartilaginous rays [syn: Malacopterygii,
         superorder Malacopterygii]