Webster’s Revised Unabridged Dictionary · 1913
Osmaterium
Os′ma·te′ri·um (ŏz′mȧ·tē′rĭ·ŭm), n.; pl. Osmateria (#). [NL., fr. Gr. ὀσμὴ smell.] (Zoöl.) One of a pair of scent organs which the larvæ of certain butterflies emit from the first body segment, either above or below.