noun
retreat (spiritual, religious)
Rare term for a religious or spiritual retreat, typically used in Christian contexts.
教会の退修会に参加した。
I participated in the church retreat.
Another term for a spiritual retreat, more common than 退修会.
Compound of 退 (retreat, withdraw), 修 (discipline, study), and 会 (gathering). The exact origin is uncertain, but it appears to be a coined term for a religious retreat.