Obsĭus | Obsĭānus, a, um | obsĭāna, ae | obsĭāna, ōrum (noun M.f) :
* A Roman surname, Plin. 36, 26, 67, § 196.—Hence, , , adj., belonging to Obsius: lapis,so named after the discoverer,Plin. 37, 10, 65, § 177.— Also subst.: , , , Plin. 37, 13, 76, § 200; and , , plur. n., a kind of glass: obsiana numerantur,id. 36, 26, 67, § 196. (The older editions of Pliny read Obsidius and Obsidianus; hence the name obsidian applied to the stone.)