NAUPACTUS, or NAUPACTUM, (anc. geogr.), the extreme or outmost town of the Ætolians, formerly belonging to the Locrians, but adjudged by Philip to the former: so called from the shipbuilding there carried on, and situated near Antirrhium on the Corinthian bay. Naupactus, the epithet. Now Leptanto, a port-town of Achaia or Livadia, on the north side of the gulf of that name. E. Long. 22. 20. N. Lat. 38. 0.