Lewis & Short

per-mūnĭo, īvi or ĭi, ītum, 4, v. a., to fortify completely, to finish fortifying (not in Cic. or Cæs.).

  1. I. Lit.: quae munimenta incohaverat, permunit, Liv. 30, 16: permunitas Athenas esse, Just. 2, 15, 9.
  2. II. Transf., in gen., to fortify completely or thoroughly: castris permunitis, Liv. 7, 16: locorum opportuna permunivit, Tac. A. 4, 24; 2, 7: urbem, Just. 24, 7, 8.