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Webster 1913 Edition
Selenite
Sel′e-nite
,Noun.
 (Chem.) 
A salt of selenious acid. 
 Sel′e-nite
,Noun.
 [L. 
selenites
, Gr. [GREEK][GREEK][GREEK][GREEK] (sc. [GREEK][GREEK][GREEK]), from σελήνη 
the moon. So called from a fancied resemblance in luster or appearance to the moon.] (Min.) 
A variety of gypsum, occuring in transparent crystals or crystalline masses. 
Webster 1828 Edition
Selenite
SEL'ENITE
,Noun.