long shot
US /ˈlɔŋ ˌʃɑt/
UK /ˈlɔŋ ˌʃɑt/

1.
渺茫的希望, 成功的机会很小
an attempt or guess that has only a small chance of success but is worth trying
:
•
It's a long shot, but we might as well try.
这成功的机会很渺茫,但我们不妨一试。
•
Winning the lottery is a complete long shot.
中彩票完全是渺茫的希望。