outrider
n. 騎馬侍從,先驅者,摩托車警衛
Outriders are people such as policemen who ride on motorcycles or horses beside or in front of an official vehicle, in order to protect the people in the vehicle.
...a black Mercedes with motorcycle outriders provided by the city's police.
由該市警方的摩托護衛為其開道的黑色梅賽德斯車
1. an escort who rides ahead (as a member of the vanguard)