游水器
Swimmeret \Swim"mer*et\, n. (Zo["o]l.) One of a series of flat, fringed, and usually bilobed, appendages, of which several pairs occur on the abdominal somites of many crustaceans. They are used as fins in swimming.
swimmeret n : one of the paired abdominal appendages of certain aquatic crustaceans that function primarily for carrying the eggs in females and are usually adapted for swimming [syn: {pleopod}]