noun
mobile police box; moving police box
A small police station built into a vehicle, used to provide police services in areas without a permanent kōban.
移動交番が毎週火曜日に駅前に来る。
The mobile police box comes to the station front every Tuesday.
A fixed neighborhood police box; 移動交番 is its mobile counterpart.
Compound of 移動 (idō, 'mobile') and 交番 (kōban, 'police box').