louver

/ˈluːvər/
noun
  1. One of a set of angled slats or strips, usually in a frame, that allow air or light to pass through while blocking rain, direct sunlight, or visibility.
    • He adjusted the louvers on the air vent to direct the cool air upward.
    • The window's louvers let in a breeze even during a light rain.
    • Each louver on the shutter was tilted to keep the afternoon sun out.
Synonyms
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