re·al·gar (rē-ălgär′, -gər)
A soft orange-red arsenic ore, As2S2, used in pyrotechnics and tanning and as a pigment.
[Middle English, from Medieval Latin, from Catalan, from Arabic rahj al-ġār, powder (of) the mine or cave : rahj, powder + al-, the + ġār, cave; see ġrr in the Appendix of Semitic roots.]
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