Chicken out Definition: T o decide not to do something because you are too frightened. (因害怕而)退縮,放棄 Usage: You back away from something because you’re scared.
Origin The expression began to gain popularity in the United States in the mid-20th century, with its roots possibly tracing back to earlier uses of "chicken" to refer to someone who is cowardly. The term captures the idea of someone being too afraid to take a risk or face a challenge, much like how a frightened chicken might flee from danger.
Sentences He chickened out right before the game. I was going to bungee jumping, but I chickened out Johnny says he is an action man but he chickened out of riding a horse.