Postilion

n.

1.

One who rides and guides the first pair of horses of a coach or post chaise; also, one who rides one of the horses when one pair only is used.

Noun

1.

postilion - someone who rides the near horse of a pair in order to guide the horses pulling a carriage (especially a carriage without a coachman) Synonyms: postillion

equestrian, horseback rider, horseman, postillion