Vocabulary What does 北海 (ほっかい, hokkai) mean? 北海 (ほっかい, hokkai) means northern sea. Quick factsReadingほっかいRomajihokkaiPart of speechnoun 北海ほっかいhokkainorthern sea1noun northern sea2noun North Sea3noun · noun prefix HokkaidoKanji in this word北north海sea