According to the "Guangyun" (Guangyun), the character is pronounced "sou" (falling tone). It is pronounced by rhyming with "suo" and "jiu" in the "Tang Yun" (Tang Yun), and with "shu" and "jiu" in the "Jiyun" (Jiyun), "Yunhui" (Yunhui), and "Zhengyun" (Zhengyun). The "Guangyun" explains "sou" as the sound of wind blowing. In Zhao Yi's "Xunfeng Fu" (Ode to the Swift Wind), it is written: "The wind blows with a whistling sound, as if singing and responding to each other. The wind swirls and drifts, its sound like singing. You want to grasp it, but cannot; you want to tie it, but cannot keep it." Zhang Zhengyuan's "Nanfeng Zhi Xun Fu" (Ode to the Warm Southern Wind) also describes "sou" as "the chill of the wind." Furthermore, the "Jiyun" (Jiyun) notes the pronunciation as "xian diao qie," which is the same as another character (original character missing). It is also noted as "suo jiu qie," pronounced the same as "sou." The meaning is the same.