Kowtow literally means "knock head" in Chinese — and a British ambassador's refusal to do it before Emperor Qianlong became a symbol of the collision between two world orders.
To act in an excessively subservient manner; historically, to kneel and touch the forehead to the ground as a sign of deep respect or submission in Chinese custom.
From Chinese 叩头/磕头 (kòutóu), literally knock-head, from 叩/磕 (kòu/kē, to knock, to strike) + 头 (tóu, head). The kowtow was a formal act of prostration in Chinese court ceremonial, requiring a person to kneel and touch their forehead to the ground, sometimes multiple times. Key roots: 叩头 (kòutóu) (Chinese: "knock-head, prostration").
The kowtow became a major diplomatic flashpoint between China and Britain. When Lord Macartney led a British embassy to Emperor Qianlong in 1793, the Chinese court demanded he perform the kowtow — full prostration, forehead to the floor, three times three. Macartney refused, offering instead to bow as he would to his own