|an extraordinary or unusual thing, person, or event; an exceptional example or instance.|
|a chattering or flighty, light-headed person.|
any of a group of clay minerals and their chemical varieties that swell in water and possess high cation-exchange capacities. The theoretical formula for montmorillonite (i.e., without structural substitutions) is (OH)4 Si8 Al4 O20nH2 O.
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