A lowly tradesman in Roman times was a caupō, and to trade or barter was to caupōnārī. From either the noun or the verb, the modern Germanic languages of Swedish, Dutch and German get their words for ‘to buy’: köpa, kopen and kaufen. What’s more, the capital of Denmark is the related ‘merchant-harbour’, Copenhagen.
From one of the Germanic languages, the Slavic family also gets its verbs for ‘to buy’.
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