Lewis & Short

prōjectĭo, ōnis, f. [proicio], a throwing forward, a stretching out.

  1. I. Lit.: brachii, i e. extension (opp. contractio), Cic. Or. 18, 59: projectiones aquae, jets, Fest. s. v. tullios, p. 352 Müll.
  2. II. Transf., concr., like projectura, a projection, in buildings; also, the right to build a projection, Dig. 43, 17, 3, §§ 5 and 6.