A flap or pouch attached to the front of men's tight breeches or hose, worn from the 15th to 17th centuries.
From cod (in the sense of scrotum or bag, from Old English) + piece. Originally practical, it became increasingly decorative and ostentatious during the Renaissance.
The codpiece went from practical necessity to such an exaggerated status symbol that 16th-century men stuffed them with silk, jewels, and padding—fashion has always been absurdly ridiculous.
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