Diodon holocanthus

from WordNet (r) 3.0 (2006)

Diodon holocanthus
    n 1: similar to but smaller than porcupinefish [syn:
         {balloonfish}, {Diodon holocanthus}]

from The Collaborative International Dictionary of English v.0.48

balloonfish \bal*loon"fish`\, balloon fish \bal*loon" fish`\
   (Zool.)
   A fish of the genus {Diodon} (such as {Diodon holocanthus})
   or the genus {Tetraodon}, having the power of distending its
   body by taking air or water into its dilatable esophagus. It
   is similar to but smaller than the porcupinefish. See
   {Globefish}, and {Bur fish}.
   [1913 Webster + WordNet 1.5]