The meaning of "on a wing and a prayer" is:
The definition of "on a wing and a prayer" is:
(idiom) with only a very small chance of success
A: How did you do on your medical school exam?
B: I got 51%
A: Do you think you will get into Harvard?
B: Only on a wing and a prayer.
The inexperienced baseball team was on a wing and a prayer as they prepared to play the defending champions.
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