endopodite

from The Century Dictionary.

• noun The inner one of the two main divisions of the typical limb of a crustacean: the opposite of exopodite.
• noun Both endopodite and exopodite are parts borne upon that part which is called the protopodite, and both are variously modified in different parts of the body of the same animal. The epipodite may become a gill, etc. The endopodite becomes in the thoracic region an ambulatory limb, and is then the ordinary “leg” or “claw” of a crab or lobster. When thus fully developed, it consists of 7 joints. These are the coxopodite, basipodite, ischiopodite, meropodite, carpopodite, propodite, and dactylopodite, named from base to tip of the leg, in Milne-Edwards's and Huxley's nomenclature. The nippers or chelæ at the end of such a developed endopodite are the sixth and seventh of its joints, namely, the propodite and its movably apposable dactylopodite.

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

• noun (Zoöl.) The internal or principal branch of the locomotive appendages of Crustacea. See maxilliped.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun biology The innermost of a two processes attached to the basal process of the limbs of some Crustacea.