An Etymological Dictionary of Astronomy and Astrophysics

1. A distinct portion, section, or division of a wall, wainscot, ceiling, door, shutter, fence, etc., especially of any surface sunk below or raised above the general level or enclosed by a frame or border.
   

2. A comparatively thin, flat piece of wood or the like, as a large piece of plywood.
   

3. A group of persons gathered to conduct a public discussion, judge a contest, serve as advisers, be players on a radio or television game, or the like (Dictionary.com).

Etymology (EN): M.E., from O.Fr. panel “a piece (of anything),” diminutive of pan “piece of cloth or the like,” ultimately from L. pannus “piece of cloth.” The sense of “a small group of people called on to discuss, judge, advice on a particular matter” is from 1570s.

Etymology (PE): Pošel, from poš, → pane, + -el, → -al.