uropod

/ˈjʊrəpɑd/
noun
  1. One of the paired appendages at the rear end of a crustacean (such as a shrimp or lobster), used for swimming or steering.
    • When threatened, a lobster fans its uropod to create a current and escape.
    • The shrimp used its uropod to dart backward through the water.
    • The biologist pointed out the uropod on the crayfish during the dissection.
What does "uropod" mean? | whatsthatwordmean | whatsthatwordmean