nephrocyte

from The Century Dictionary.

• noun An excretory cell, with fibrillar or vacuolated cytoplasm, which contains masses of waste products. Such cells occur in the track of the blood-currents in the Crustacea.

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

• noun biology a specialized cell, especially in arthropods, whose function involves the accumulation or formation of waste or excretory products