|an extraordinary or unusual thing, person, or event; an exceptional example or instance.|
|a chattering or flighty, light-headed person.|
(species Addax nasomaculatus), desert-dwelling antelope, family Bovidae (order Artiodactyla), once found throughout the Sahara but now much reduced in numbers and distribution and threatened with extinction from overhunting. A heavy-bodied, short-legged, gregarious antelope, the addax is characterized by broad hooves that are adapted to travel in loose sand and by long, spirally twisted horns, present in both sexes. It stands approximately 1 m (39 inches) high at the shoulder and is grayish in summer, darker in winter. Its legs, underparts, and a patch on the face are white, and there is a tuft of dark hair on the forehead.
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