flap

柯林斯词典

1. V-T/V-I If something such as a piece of cloth or paper flaps or if you flap it, it moves quickly up and down or from side to side. 使快速摆动; 快速摆动
Grey sheets flapped on the clothes line. 灰色的床单在晾衣绳上飘动。
2. V-T/V-I If a bird or insect flaps its wings or if its wings flap, the wings move quickly up and down. 快速振动 (翅膀)
The bird flapped its wings furiously. 那只鸟儿使劲地拍打着翅膀。
3. V-T If you flap your arms, you move them quickly up and down as if they were the wings of a bird. (双臂像小鸟般) 扇动
...a kid running and flapping her arms. …一个边跑边像小鸟一样上下扇动着双臂的小女孩。
4. N-COUNT A flap of cloth or skin, for example, is a flat piece of it that can move freely up and down or from side to side because it is held or attached by only one edge. (一端固定、可自由掀动的布或皮的) 垂悬平片
He drew back the tent flap and strode out into the blizzard. 他拉开帐篷的门帘，大步走进了暴风雪中。
5. N-COUNT A flap on the wing of an aircraft is an area along the edge of the wing that can be raised or lowered to control the movement of the aircraft. (飞机的) 副翼
...the sudden slowing as the flaps were lowered. …副翼降下时的突然减速。