This is a line from the movie "Tong Pak Hu Dian Qiu Xiang".
Tsing lung and white tiger are also the favorite patterns of tattooers.
In "Tong Pak Hu Dian Qiu Xiang", the master pulled out a machete, but the popular "old cow" refers to a horn knife.
Ancient props commonly used in Guangdong, Guangxi, Yunnan and other places, commonly known as "Niubaiye", belong to folding knives. A long time ago, its handle was mostly made of buffalo horn, and the back was locked, so it could be firmly fixed when it was opened. In the past, people who mixed with society always pinned a knife to their waist, which is what the movie said: "The old cow is on the waist."
Extended data:
There are four legendary beasts in China: Qinglong, Baihu, Suzaku and Xuanwu. Qinglong is the God of the East; White tiger is the god of the west; Zhu is known as the god of the south; Xuanwu is the god of the north.
Usually, the left green dragon and the right white tiger represent the left and right positions, not the real green dragon and white tiger.
Qinglong represents the East and White Tiger represents the West.
In addition to the four spirits in Taoism, including dragons and white tigers, and even when Feng Shui masters explore cemeteries, the terrain protruding from the left and right sides in front of the terrain can be used as burial rooms, which have unique titles, called Zuo Qinglong and Right White Tiger, to take the meaning of their guards, and also have the same decoration in the court. The left and right pillars are painted with dragons and white tigers to suppress evil spirits.
Baidu Encyclopedia-Left Qinglong Right White Tiger