balance beam

balance-beam的词性：
n.Sports （名词）【体育运动】

1. A horizontal, raised beam with a width of 10 centimeters (4 inches) and a length of 5 meters (16 feet) that is used in gymnastic competition for balancing exercises.
平衡木：一块宽10厘米（4英寸）、长5米（16英尺）水平升起的木板，用于平衡运动的体育比赛

2. A competitive gymnastics event in which various balancing feats are performed on this beam.
平衡木比赛：在平衡木上做各种平衡技巧表演的体育比赛