The geoduck ("gooey duck"), Panopea abrupta,'s a species of very large saltwater clam, a marine bivalve mollusk in the family Hiatellidae. The shell of this clam's large, about 15 to over 20 cm in length (about 7 to 9 inches), but the extremely long siphons make the clam itself very much longer than this: the "neck" or siphons alone can be one meter in length. Etymology The unusual name of the clam's derived from a Lushootseed (Nisqually) word gʷídəq meaning "dig deep", and its… (More on Geoduck)