Answer: getahorse

AnswerCrossword Clue
GETAHORSE

Old-time advice to a motorist.

GETAHORSE

Bon mot to a motorist, circa 1900.

GETAHORSE

Exhortation from early Maxwell days.

GETAHORSE
Advice to a pony-car owner?
GETAHORSE
Taunt to an early motorist
GETAHORSETaunt in early motoring