8 letters · 13 points in Scrabble
noun marine crustaceans with feathery food-catching appendages; free-swimming as larvae; as adults form a hard shell and live attached to submerged surfaces
originBorrowed from translingual Cirripedia. By surface analysis, cirri- + -ped. Doublet of cirripede.
Etymology from Wiktionary, CC BY-SA 3.0