skimmer
skim·mer / ˈskimər/ • n. 1. a person or thing that skims, in particular: ∎ a utensil or device for removing a substance from the surface of a liquid. ∎ a device or craft designed to collect oil spilled on water. ∎ a hydroplane, hydrofoil, hovercraft, or other vessel that has little or no displacement when traveling. 2. a long-winged seabird (genus Rynchops) related to the terns, feeding by flying low over the water surface with its knifelike extended lower mandible immersed. 3. a flat, broad-brimmed straw hat. 4. a broad-bodied dragonfly (Libellulidae and related families) commonly found at ponds and swamps. It can rest for long periods on a perch, from which it darts out to grab prey. Several genera and numerous species include the twelve-spotted skimmer (Libellula pulchella).