noun
coachman; driver of a horse-drawn carriage
Refers specifically to the person who drives a horse-drawn vehicle such as a carriage or coach. Not used for modern automobile drivers.
御者が馬車を止めて、客を降ろした。
The coachman stopped the carriage and let the passenger off.
昔の映画では、御者が長い鞭を持っている。
In old movies, the coachman holds a long whip.
Refers to a driver of a modern vehicle (car, bus, etc.), while 御者 is specifically for horse-drawn carriages.
Compound of 御 (honorific prefix) and 者 (person), literally 'honorable person who drives'. The kanji 馭 in the variant 馭者 specifically means 'to drive a horse'.