arsenic
Cross references:
1. element
1. ar.se.nic \'a:rs-nik, -*n-ik\ n [ME, fr. MF & L; MF, fr. L arsenicum,
fr. Gk arsenikon, arrhenik]on yellow orpiment, fr. Syr zarni-g, of Iranian
origin; akin to Av zaranya gold, Skt hari yellowish - more at YELLOW 1: a
trivalent and pentavalent solid poisonous element commonly metallic st
eel-gray, crystalline, and brittle 2: a poisonous trioxide As2O3 or As4O6
of arsenic u sed esp. As an insecticide or weed killer - called also
arsenic trioxide
2. ar.sen.ic \a:r-'sen-ik\ aj : of, relating to, or containing arsenic esp.
with a valence of five