Comma,

Comma - Date of Origin 16th c.

Greek kómma meant literally ‘piece cut off, segment’. It derived from the verb kóptein ‘cut’, relatives of which include Russian kopje ‘lance’, source of the coin-name kopeck, and probably English capon. Kómma came to be applied metaphorically, as a technical term in prosody, to a small piece of a sentence, a ‘short clause’, a sense which it retained when it reached English via Latin comma. It was not long before, like colon, it was applied to the punctuation mark signifying the end of such a clause.

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