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(fixing) boundaries for religious practices
prohibition (of items, people, spirits, etc. that would hinder Buddhist practice)
fence between inner and outer sanctums in a temple
barrier; dimensional barrier; containment zone; containment barrier; mystical barrier
僧侶は結界を張った。
The monk set up a sacred barrier.
敵から身を守るため、結界が張られた。
A barrier was erected to protect us from enemies.
封印されていた結界が解け、魔物が世界に溢れ出した。
The sealed barrier broke, and monsters flooded the world.