Lewis & Short

suppŏsĭtīcĭus (subpŏs-) or -tĭus, a, um, adj. [suppono, I. B.], put in the place of another, substituted.

  1. * I. In gen.: Hermes supposititius sibi ipsi, is his own substitute, i. e. he needs no one to replace him in combat, Mart. 5, 24, 8.
  2. II. In partic., not genuine, false, supposititious: mater, Varr. R. R. 2, 8, 2: explorator, Plaut. Ps. 4, 7, 71.