"Zu" is the chopping board used for cutting meat in ancient times. The literal meaning is that others are like the knife and chopping board for cutting meat, and I am the fish on the chopping board. It is a metaphor that the power of life and death is in the hands of others, and you are in a position of being slaughtered.

Source: "Historical Records of Xiang Yu" written by Sima Qian of the Western Han Dynasty: "The great conduct does not care about the meticulousness, and the great gifts do not hesitate to make small concessions. Nowadays, people are like swordsmen, and I am like fish and meat, so why should I refuse."

Extended information:

Story background:

The famous story "Hongmen Banquet" in "Historical Records·The Chronicles of Xiang Yu" writes: Because Liu Bang, Xiang Yu and King Huai had "predecessor" After entering Guanzhong, Liu Bang occupied Xianyang, sealed up the Qin palace treasury and wanted to take it as his own, and garrisoned troops to guard Hangu Pass and prevent Xiang Yu from entering the pass.

Xiang Yu, who arrived later, led 400,000 troops to garrison at Xinfenghongmen. Liu Bang's Bashang garrison only had 100,000 troops. No matter how large the troops were, Liu Bang's army could not withstand the powerful Chu army.

Seeing that he was about to be slaughtered, Liu Bang could only seek reconciliation with clever words. So Xiang Yu invited Liu Bang to a banquet at Hongmen. Although Xiang Yu was persuaded at the Hongmen Banquet, Fan Zeng wanted to kill Liu Bang to avoid future troubles, so he repeatedly tried to attack Liu Bang. The situation was very threatening. This situation was like Liu Bang being put on the chopping board as fish and meat, with nowhere to go. He can escape, but Xiang Yu and Fan Zeng are like chefs holding sharp knives. If they want, they can chop Liu Bang into powder with one knife.

Reference material: People are treated as knives and fish as meat - Baidu Encyclopedia