emydea

from The Century Dictionary.

• The name given by Huxley to a group of the Chelonia, having usually horny cutting jaws, uncovered by lips, the tympanum exposed, the limbs slenderer than in Testudinea, with 5-clawed digits united by a web only, and the horny plates of the carapace and plastron well developed.

from the GNU version of the Collaborative International Dictionary of English.

• noun plural (Zoöl.) A group of chelonians which comprises many species of fresh-water tortoises and terrapins.