noun. An event, especially a confrontation, that forces an issue to a conclusion.

noun. The laying down of the players' cards face up to determine the winner of the pot in poker.

noun. The final battle between two nemeses, in which there can be but one victor

noun. The final round in a poker match, where the all remaining players' cards have to be put down on the table and shown

noun. a hostile disagreement face-to-face

"Chelsea's loss to Liverpool this month means the game can no longer be seen as the title showdown Carlo Ancelotti had been hoping, but with Arsenal in such close pursuit United can ill afford to drop points anywhere."

disagreement  

godown  hoedown  lowdown  slowdown  

clincher  confrontation  life-or-death  match-up  matchup  

antagonism  antipathy  antithesis  clashing  climax