The Collaborative International Dictionary of English v.0.48:

Pail \Pail\ (p[=a]l), n. [OE. paile, AS. p[ae]gel a wine vessel,
   a pail, akin to D. & G. pegel a watermark, a gauge rod, a
   measure of wine, Dan. p[ae]gel half a pint.]
   A vessel of wood or tin, etc., usually cylindrical and having
   a bail, -- used esp. for carrying liquids, as water or milk,
   etc.; a bucket. It may, or may not, have a cover. --Shak.
   [1913 Webster]

WordNet (r) 3.0 (2006):

pail
    n 1: a roughly cylindrical vessel that is open at the top [syn:
         bucket, pail]
    2: the quantity contained in a pail [syn: pail, pailful]