| a screen or mat covered with a dark material for shielding a camera lens from excess light or glare. |
| the offspring of a zebra and a donkey. |
air lock
device that permits passage between regions of differing air pressures, most often used for passage between atmospheric pressure and chambers in which the air is compressed, such as pneumatic caissons and underwater tunnels. The air lock also has been used as a design feature of space vehicles; on March 18, 1965, the Soviet cosmonaut Aleksey Leonov passed through an air lock to become the first man to walk in space
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