The surname of BALLESTY was an occupational name for a maker of crossbows, or for a soldier armed with a crossbow, originally derived from the Old French word BALESTE and rendered in medieval documents in the Latin form BALLISTA, meaning military.

During the Middle Ages, in Spain and Portugal the name came to be used as the title of a minister who slept in a room adjoining his master's, originally as a kind of bodyguard, and also of various other court officials involved in royal ceremonies.