reservation system; appointment system; subscription basis
Refers to a system or arrangement where advance booking, appointments, or subscriptions are required or used. Often seen in phrases like 予約制のレストラン (a reservation-only restaurant) or 予約制のサービス (a subscription-based service).
This clinic operates on a completely appointment-based system.
The popular restaurant is reservation-only, so please call in advance.
reservations-only system; by-appointment-only system
Compound of 予約 (reservation, appointment) and 制 (system, rule). The exact historical derivation is straightforward; the word follows a common pattern for describing institutional systems.