Arsenic

(123) (Synop., §130), n. [Fr. arsenic, Pr. arsenic, Lat. arsenicum, Gr. ἀρσενικόν, ἀρρενικόν, yellow orpiment, arsenic, from ἀρρενικός, masculine, ἄρρην, male, on account of its strength.]

1. (Min.) A metal of a steel gray color, and brilliant luster, though usually dull from tarnish. It is very brittle, and sublimes at 356° Fahrenheit. Specific gravity from 5.7 to 5.9. It is sometimes found native, but usually combined with silver, cobalt, nickel, iron, antimony, and sulphur. Orpiment and realgar are two of its sulphur compounds. Orpiment is the true arsenicum of the ancients. Plin. 34, 18.
2. (Com.) Arsenious acid:—called also oxide of arsenic, white arsenic, and ratsbane. Dana.