Stack  —n. 1 (esp. Orderly) pile or heap. 2 = *haystack. 3 colloq. Large quantity (a stack of work; stacks of money). 4 a = *chimney-stack. B = *smokestack. C tall factory chimney. 5 stacked group of aircraft. 6 part of a library where books are compactly stored. 7 high detached rock, esp. Off the coast of scotland. —v. 1 pile in a stack or stacks. 2 a arrange (cards) secretly for cheating. B manipulate (circumstances etc.) To suit one. 3 cause (aircraft) to fly in circles while waiting to land. [old norse]