Importuosus, pe. pro. Adiect. Pli. iun Without port or hauen.Mare sæuum & importuosum.Salust.A daungerous sea and without succour of hauens.Littora importuosa.Liu.
Lewis and Short: Latin dictionary
importŭōsus (inp-), a, um, adj. [2. in-portuosus], without a harbor: mare, Sall. J. 17, 5: laeva inportuosa Italiae litora, Liv. 10, 2, 4; Tac. A. 4, 67: litus, Plin. Ep. 6, 31, 17: insula importuosissima omnium, Plin. 4, 12, 23, 73.