aigéan
Definitions (by source)
m., ocean, depth, 2081, 8999; also aigian, 7468; 7839; 10374 (pit of hell); oigéan, 2276; oigian, 3550; gen. aigéin, 2147
Trí Bior-Ghaoithe an Bháis: The Three Shafts of Death. Editor: Osborn Bergin.