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late 14c., from Old French arsenic, from Latin arsenicum, from late Greek arsenikon "arsenic" (Dioscorides; Aristotle has it as sandarake), adapted from Syriac (al) zarniqa "arsenic," from Middle Persian zarnik "gold-colored" (arsenic trisulphide has a lemon-yellow color), from Old Iranian *zarna- "golden," from PIE root *ghel- "to shine" (see Chloe).
The form of the Greek word is folk etymology, literally "masculine," from arsen "male, strong, virile" (cf. arseno-koites "lying with men" in New Testament) supposedly in reference to the powerful properties of the substance. The mineral (as opposed to the element) is properly orpiment, from Latin auri pigmentum, so called because it was used to make golden dyes.
arsenic ar·se·nic (är'sə-nĭk)
A poisonous metallic element having three allotropes, of which the gray form is the most common. Arsenic compounds are used in insecticides and solid-state doping agents. Atomic number 33; atomic weight 74.922; valence 3, 5. Gray arsenic melts at 817°C (at 28 atm pressure), sublimes at 614°C, and has a specific gravity of 5.73. adj. ar·sen·ic (är-sěn'ĭk)
Of or containing arsenic, especially with valence 5.
A metalloid element most commonly occurring as a gray crystal, but also found as a yellow crystal and in other forms. Arsenic and its compounds are highly poisonous and are used to make insecticides, weed killers, and various alloys. Atomic number 33; atomic weight 74.922; valence 3, 5. Gray arsenic melts at 817°C (at 28 atm pressure), sublimes at 613°C, and has a specific gravity of 5.73. See Periodic Table.