It is an onomatopoeia of slap, because it cannot be expressed in Chinese characters, as it means "beat".

Other meanings of pai:

1. Pai is pi: π

Pi is represented by the Greek letter π (pronounced [pa?]), which is a The constant (approximately equal to 3.141592653) represents the ratio of the circumference and diameter of a circle. It is an irrational number, that is, an infinite non-repeating decimal.

In daily life, 3.14 is usually used to represent pi for approximate calculations. Using ten decimal places, 3.141592653 is sufficient for general calculations. Even if engineers or physicists want to perform more precise calculations, they only need to take values ??to a few hundred decimal places at best.

2. Pai means that music belongs to: beat

Music beat refers to the combination law of strong beat and weak beat, specifically the total length of notes in each section of the score, which is common. Beats of 1/4, 2/4, 3/4, 4/4, 3/8, 6/8, 7/8, 9/8, 12/8, etc., the length of each measure is fixed. The tempo of a piece of music is fixed at the time of composition and will not change. A piece of music can be composed of a combination of several beats.

3. Pai is an e-commerce term: take a photo of the baby

"Shoot the baby" specifically refers to online trading platforms (such as Baidu Youah, Taobao, eBay, Paipai.com) etc.). "Baby" is a commodity. Taking photos refers to the process from purchasing goods to payment to the trading platform.