Entry 1 sense Webster, 1913 Culvert /(k?l"v?rt)/ · Cul·vert · IPA /ˈkʌlvə(ɹ)t/ 01 n. A transverse drain or waterway of masonry under a road, railroad, canal, etc.; a small bridge. 1. A transverse drain or waterway of masonry under a road, railroad, canal, etc.; a small bridge.