/pil"yeuhn/ , n.
1. a pad or cushion attached behind a saddle, esp. as a seat for a woman.
2. a pad, cushion, saddle, or the like, used as a passenger seat on a bicycle, motor scooter, etc.
3. a passenger's saddle or seat behind the driver's seat on a motorcycle.
[ 1495-1505; pillinn or Ir pillín, dim. of peall skin, rug blanket, MIr pell pellis skin ]