[1] : The Collaborative International Dictionary of English v.0.48

quintain \quin"tain\, n. f. quintaine, ll. quintana; cf. w.
   chwintan a kind of hymeneal game.
   an object to be tilted at; -- called also quintel. written
   also quintin.
   1913 webster

   note: a common form in the middle ages was an upright post,
         on the top of which turned a crosspiece, having on one
         end a broad board, and on the other a sand bag. the
         endeavor was to strike the board with the lance while
         riding under, and get away without being hit by the
         sand bag. "but a quintain, a mere lifeless block."
         --shak.
         1913 webster
see also:
quintel quintin 

Quintain >> Q Words
Quintain, definition of term: Quintain
quintain_pag1.html