Casserian,a.|kæˈsɪərɪən| [According to Syd. Soc.Lex. from Giulio Casserio of Piacenza, 1545–1616.] Casserian (or Gasserian) ganglion: the ganglion of the larger root of the fifth nerve. 1842E. Wilson Anat. Vade Mec. 407 It arises from the upper angle of the Casserian ganglion.