1. A pad or cushion for an extra rider behind the saddle on a horse or motorcycle.
2. A bicycle or motorcycle saddle.

[Probably from Scottish Gaelic pillean, diminutive of peall, rug, or Irish Gaelic pillín, diminutive of pell, rug, both from Old Irish pell, from Latin pellis, animal skin.]

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.