Portus

From the Latin Portus, presumably from portus (“harbour, port”).

• (Received Pronunciation, UK) IPA^(key): /ˈpɔːtəs/

Portus

1. (historical, Roman Empire) A large artificial harbour of Ancient Rome, situated on the north bank of the mouth of the River Tiber, established and enlarged (respectively) by the Emperors Claudius (10 BC–AD 54) and Trajan (AD 53–117), and connected to the Pons Aemilius of Rome by the Via Portuensis.

• Ostia

• Portus on Wikipedia.Wikipedia

• Proust, Sprout, Stroup, Troups, sprout, stupor

Presumably a use as a proper noun of the common noun portus (“harbour”, “port”).

• (Classical) IPA^(key): /ˈpor.tus/, [ˈpɔr.tʊs]
• Homophone: portus

Portus m (genitive Portūs); fourth declension

1. (more fully “Portus Ostiēnsis Augustī” or, later, “Portus Rōmae”) Portus (large artificial harbour of Ancient Rome)

Fourth declension, with locative.

• English: Portus
• Italian: Porto

• Ostia