What do you call the second person on a motorcycle?

What do you call the second person on a motorcycle?

A pillion is a secondary pad, cushion, or seat behind the main seat or saddle on a horse, motorcycle, bicycle or moped. A passenger in this seat is said to “”ride pillion””. The word is derived from the Scottish Gaelic for “”little rug””, pillean, from the Latin pellis, “”animal skin””.