A bulging lens used to bring together the rays of light from a lamp upon a small spot; also, a lantern having such a lens.

(聚光的)凸透镜:有凸透镜之灯笼。

A round piece of thick glass in a floor or deck to admit light.

(采光用)牛眼窗；【建】小圆窗；舷窗玻璃。

The center of a target, or a shot that hits it.

靶心；中的之射击。