sĕlēnītis

ĭdis, f.
I. crystalline gypsum, selenite. Form selenitis, Plin. 37, 10, 67, § 181; form selenites, Sol. 37, 31; Aug. Civ. Dei, 21, 5; Isid. 16, 4, 6.
Lewis & Short
A Latin Dictionary, 1879
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