名詞 louver:

1. one of a set of parallel slats in a door or window to admit air and reject rain
   同義詞：louvre, fin

louver 也作 lou.vre

n.（名詞）

A framed opening, as in a wall, door, or window, fitted with fixed or movable horizontal slats for admitting air and light and shedding rain.
固定百葉窗：一個有框架的開口處，比如在一堵墻里，門里或窗戶里。安裝有固定的或活動的水平條板，用來通風、采光、遮雨
One of the slats used in such an opening.
百葉窗板：用在這種開口的條板
One of the narrow openings formed by such slats.
條百頁：由這種條板組成的狹窄開口
A slatted, ventilating opening, as on the hood of a motor vehicle.
放氣孔：有條板的換氣口，比如在車輛的引擎蓋上
A lantern-shaped cupola on the roof of a medieval building for admitting air and providing for the escape of smoke.
天窗：中世紀建筑屋頂上的燈籠狀的小塔，用來通風，冒煙

來源：
Middle English lover [skylight, chimney]
中古英語 lover [天光，煙囪]
from Old French
源自 古法語
from Middle Dutch love [gallery]
源自 中古荷蘭語 love [美術館]
from Middle High German lauble
源自 中古高地德語 lauble

【引伸】
lou.vered
adj.（形容詞）