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portŭōsus, a, um, adj. [portus], full of or abounding in harbors, having many harbors: mare, Cic. de Or. 3, 19, 69: flumen Trinium, Plin. 3, 12, 17, § 106: pars Numidiae portuosior, Sall. J. 16, 5: navigatio minime portuosa, with no ports to run into, Cic. Fam. 6, 20, 1.
* Adv.: portŭōsē, with many harbors; only comp.: portuosius illic alveus Nili, with more harbors, Jul. Val. Rer. Gest. Alex. M. 1, 20 fin. Mai.