The Collaborative International Dictionary of English v.0.48:

Stymie \Sty"mie\, n. Also Stimy \Sti"my\ . [Orig. uncertain.]
   (Golf)
   The position of two balls on the putting green such that,
   being more than six inches apart, one ball lies directly
   between the other and the hole at which the latter must be
   played; also, the act of bringing the balls into this
   position.
   [Webster 1913 Suppl.] Stymie

The Collaborative International Dictionary of English v.0.48:

Stymie \Sty"mie\, v. t. Also Stimy \Sti"my\ . (Golf)
   To bring into the position of, or impede by, a stymie.
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

stymie
    n 1: a situation in golf where an opponent's ball blocks the
         line between your ball and the hole [syn: stymie,
         stymy]
    2: a thwarting and distressing situation [syn: stymie,
       stymy]
    v 1: hinder or prevent the progress or accomplishment of; "His
         brother blocked him at every turn" [syn: obstruct,
         blockade, block, hinder, stymie, stymy,
         embarrass]

Moby Thesaurus II by Grady Ward, 1.0:

22 Moby Thesaurus words for "stymie":
   block, brake, confound, deadlock, defeat, flummox, foil, frustrate,
   halt, hinder, impede, nonplus, obstruct, ruin, slow down, snooker,
   spike, stall, stay, stop, stump, thwart