Lewis & Short

praepŏsĭtĭo, ōnis, f. [praepono].

  1. I. A putting or setting before, a preferring, preference, Cic. Fin. 3, 16, 54.
  2. II. A placing or setting over as commander or president, an appointing to command (postclass.): aliquem navi, Dig. 14, 1, 1, § 12.
  3. III. In gram., a preposition, Cic. Or. 47, 158; cf.: praeposito in privatur verbum eā vi, quam haberet, si in praepositum non fuisset, id. Top. 11: cum praepositione dicitur volgo ornamentum, Varr. L. L. 6, § 76 Müll.; Quint. 1, 4, 13 et saep.