geoduck

An Americanism dating back to 1880–85; from Lushootseed (formerly Puget Salish ) gwídəq, of uncertain meaning: either an element gwíd-, of uncertain origin + -əq “genitals” (from the resemblance of the siphon to a penis), or from a phrase meaning “dig deep” (because the mollusk buries itself up to three feet deep in sand, silt, or gravel)

All agree that the word geoduck originated in a Native American Salish language of the Pacific Northwest. Some say (as at Evergreen State College in Washington State where the official school mascot is a geoduck) that it means “dig deep,” but others say the final -əq of the Salish word gwídəq means “genitals.” Since ESC's motto is “Let It All Hang Out,” they seem happy to embrace both aspects of this unusual creature. How the [goo-ee] /ˈgu i/ sound came to be spelled geo is anyone's guess, but it's most likely a European interpretation of the Salish pronunciation.
What you choose to believe is up to you, but just don't call it a JEE-oh-duhk.