leatherback definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
the only species (Dermochelys coriacea) of a family (Dermochelyidae) of tropical sea turtles, covered with a tough, leathery upper shell: it is the largest living turtle, weighing up to c. 725 kg (c. 1,600 lb)
leatherback definition by American Heritage Dictionary
The largest living sea turtle (Dermochelys coriacea), found in tropical waters and having a tough, leathery carapace with seven longitudinal ridges.