First recorded around 1400–50.
Comes from the late Middle English word ferdkyn or firdekyn.
This is formed from a variant of ferthe, meaning "fourth," and the diminutive suffix -kin.
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EXAMPLES OF FIRKIN

The antique store had a collection of quaint firkins on display, each with its own unique design.
After the harvest festival, the townspeople gathered around to share stories over slices of bread from a firkin of butter.

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