Lewis & Short

ossŭārĭus, a, um, adj. [2. os],

  1. I. of or for bones, bone- (post-class.): OLLA OSSVARIA, a vase to contain the bones of a corpse, a bone-urn, Inscr. Orell. 2896.
  2. II. Subst.: ossŭārĭum (also written ossārĭum), ii, n., a receptacle for the bones of the dead, a bone-vault, charnel-house, Dig. 47, 12, 2; Inscr. Orell. 4511; 4556.