noun
boundary between the human world and the realm of the sea god
Mythological term from Japanese folklore, referring to the liminal space where the ordinary world meets the domain of the sea deity (often associated with Ryūgū-jō). Rare in modern usage outside of traditional stories or poetic contexts.
浦島太郎は海境を越えて竜宮城へ行ったと伝えられる。
It is said that Urashima Tarō crossed the boundary to the sea god's realm and went to Ryūgū-jō.
この浜は海境に近い神聖な場所とされてきた。
This beach has been regarded as a sacred place near the boundary of the sea god's world.
Compound of 海 (umi, 'sea') and 境 (sakai, 'boundary'), with a sound shift from umisakai to unasaka. The exact historical derivation is uncertain, but the term appears in classical Japanese texts referring to the mythical divide between the human world and the sea god's realm.