Traditional Chinese medicine believes bull pizzle can tonify the kidneys.
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Strictly a culinary / TCM term. Comes up on exotic menus and in 'kidney-tonifying' (补肾) folk medicine, almost never in everyday conversation. Foreigners are sometimes served it as a test.
culture
Animal genitalia (牛鞭, 鹿鞭, 狗鞭) are valued in Chinese folk medicine for supposed yang-tonifying effects. The character 鞭 ('whip') is a euphemism for the shape.
