noun, plural os·ti·a [os-tee-uh] /ˈɒs ti ə/.
Origin of ostium
Examples from the Web for ostia
Like many discoveries, the new part of Ostia Antica was found by accident.
On the third day after the tumult, Genseric boldly advanced from the port of Ostia to the gates of the defenceless city.The History of The Decline and Fall of the Roman Empire|Edward Gibbon
In the first ship which sails from Ostia for any port of Greece, in that ship you may depart.
There is abundant evidence that all through the second century of our ra great architectural works were carried on at Ostia.