• WordNet 3.6
    • n balloonfish similar to but smaller than porcupinefish
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Webster's Revised Unabridged Dictionary
    • balloonfish (Zoöl) A fish of the genus Diodonsuch 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.
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Century Dictionary and Cyclopedia
    • n balloonfish A globefish; a fish of the order Plectognathi and suborder Gymnodontes, as the tropical Tetraodon lineatus, or striped spine-belly, or a species of one of the genera Triodon and Diodon. So called because it has the power of swallowing air, which is retained in a dilatation of the esophagus, and thus of blowing itself up into a nearly spherical shape like a balloon. The ivory-like tips of the jawbones cleft above and below, as in Tetraodon, give the fish the appearance of having four teeth, two above and two below. See Gymnodontidæ.
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