An Etymological Dictionary of Astronomy and Astrophysics

1. A portion of an object or of material, produced by cutting, tearing, or breaking the whole.
   

   2. An item forming part of a set.
      

   3. A written, musical, or artistic creation (OxfordDictionaries.com).

Etymology (EN): M.E. pece, peece, from O.Fr. piece, from V.L. *pettia, probably from Gaulish (cf. Welsh peth “thing;” Breton pez “piece”).

Etymology (PE): Teké “piece, patch.”