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under wraps –adj. something that is being withheld or hidden for a later time
holy grail – (literary) n. something that is greatly desired but is very hard to get
mast – n. a tall pole on a sailing ship that supports a sail or sails
sonar – n. a device that uses sound waves to find things underwater
engravings –n. details that are cut into the surface of wood, stone or metal
cannon – n. a large, heavy run
sediment – n. material that sinks to the bottom of water forming a layer
gratification – n. a feeling of being happy or satisfied with something
moment – n. a point in time
exploit – v. to use up, often in an unfair way
