"testicles," early 14c., from plural of ball (n.1). See also ballocks. Meaning "courage, nerve" is from 1928. Balls to the wall, however, probably is from World War II Air Forces slang, from the ball that topped the aircraft throttle, thrust to the bulkhead of the cockpit to attain full speed. Ball-busting "difficult" is first recorded 1944; ball-buster, disparaging for "dominant female," is from 1974.
双语例句
1. To improve hand-eye co-ordination, practise throwing and catching balls.
要想提高手眼协调能力，就练习投球和接球。
来自柯林斯例句
2. I listened to the thwack of the metal balls.
我听着金属球相撞的声音。
来自柯林斯例句
3. I never had the balls to do anything like this.
我从来没胆量做这种事。
来自柯林斯例句
4. Using 2 spoons, mould the cheese mixture into small balls or ovals.
