||Tri*on"yx (?), n. [NL., fr. Gr. &?; (see Tri-) + &?; a claw.] (Zoöl.) A genus of fresh-water or river turtles which have the shell imperfectly developed and covered with a soft leathery skin. They are noted for their agility and rapacity. Called also soft tortoise, soft-shell tortoise, and mud turtle.

&fist; The common American species (Trionyx, or Aspidonectus, ferox) becomes over a foot in length and is very voracious. Similar species are found in Asia and Africa.

||Tri*on"yx (?), n. [NL., fr. Gr. &?; (see Tri-) + &?; a claw.] (Zoöl.) A genus of fresh-water or river turtles which have the shell imperfectly developed and covered with a soft leathery skin. They are noted for their agility and rapacity. Called also soft tortoise, soft-shell tortoise, and mud turtle.

&fist; The common American species (Trionyx, or Aspidonectus, ferox) becomes over a foot in length and is very voracious. Similar species are found in Asia and Africa.