1. The act, process and method of extracting fluid from a body cavity or wound by suction or gravity in medicine. 2. The act of transmitting (such as pumping water through a pipeline). 3. It is extended to the meaning of attracting traffic in network language.

Drainage in the Chinese Dictionary refers to the drainage of fluid from wounds, abscesses, cystic glands or body cavities. The drainage itself is a foreign body, and if it is left in the body for too long, it may infect the surroundings of the drainage. Therefore, the drainage gauze placed in the injured mouth should be changed every day and the local area should be strictly disinfected. Because the drainage tube placed in the body is not easy to replace, it is usually kept for several days according to the treatment needs.

Network language drainage is to attract traffic, that is, to make it visible to more people. In a word, you let others add your WeChat or contact you in some way through various practical promotion and drainage methods. This process can be called drainage. Drainage and promotion are somewhat similar, but they are not exactly the same. It is more difficult and wider to popularize, and drainage belongs to a subdivision of popularization.