Undulipodium (pl. undulipodia) A whiplike organelle that protrudes from a eukaryotic cell and is used chiefly for locomotion (e.g. motile gametes) or feeding (e.g. ciliate protoctists).
With a whiplike movement, Crabbe pointed his wand at the fifty foot mountain of old furniture, of broken trunks, of old books and robes and unidentifiable junk, and shouted, " Descendo! "