|a chattering or flighty, light-headed person.|
|an arrangement of five objects, as trees, in a square or rectangle, one at each corner and one in the middle.|
synthetically produced aluminum oxide (Al2O3), a white or nearly colourless crystalline substance that is used as a starting material for the smelting of aluminum metal. It also serves as the raw material for a broad range of advanced ceramic products and as an active agent in chemical processing.
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