underdog

noun

1. A competitor thought unlikely to win.

   “They were the underdogs in the basketball competition.”

   “In Athens, the Americans are underdogs to the Chinese and the Canadians (the Canadians!)”

   “The visit of a Championship side would not normally send a shiver down their spine but they knew that Wigan were underdogs who would snap at their heels and that they possessed a potent bite if they were not kept on a firm leash.”

2. Somebody at a disadvantage.

   “Laszlo: Isn't it strange that you always happened to be fighting on the side of the underdog? Rick: Yes. I found that a very expensive hobby, too. But then I never was much of a businessman.”

3. A high swing wherein the person pushing the swing runs beneath the swing while the person being pushed is at the forward limit of the arc.