Because the southern astrology looks like a big bird, it is called "Southern Suzaku". Similarly, North Xuanwu, East Qinglong and West White Tiger are also named in this way.
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For South Suzaku, North Xuanwu, East Qinglong and West White Tiger, some people also call them former Suzaku, Back Xuanwu, Left Qinglong and Right White Tiger, which is a way to refer to orientation in Feng Shui. Because the south is hot, the five elements belong to fire, so it is called Suzaku; It is cold in the north, and the five elements belong to water, so it is called Xuanwu; The oriental five elements belong to wood and are green, so they are called Qinglong; The western five elements belong to gold and white, so they are called white tigers.