Any long, slender, worm-shaped bivalve mollusk of Teredo andallied genera. The shipworms burrow in wood, and are destructive towooden ships, piles of wharves, etc. See Teredo.
a type of mollusc (= a type of creature that has a soft body, no spine , and is often covered with a shell) that lives in the sea and that can damage wooden structures by making holes in them: