colon

The English word colon goes back to ancient Greek kolon. In early Greek, kolon named a limb or a distinct part of the body. By extension, it came to mean a section or member of a larger whole. That shift from flesh to structure happened well before punctuation entered the story.

Greek writers then used kolon for a member of a sentence or a measured clause in rhetoric. In Athens by the 4th century BCE, the word could describe a verbal unit with its own cadence. The same habit appears in grammatical traditions that treated speech as something built in parts. A bodily segment had become a textual segment.

Latin borrowed the term as colon and kept that grammatical sense. Roman grammarians used it for a clause or division in writing and speech. Late antique and medieval scribes then attached the name to a punctuation mark that separated such units. The sign inherited the name of the thing it marked.

English took colon from Latin and French learned usage in the 16th century. By 1547 it appears as the name of the punctuation mark, and later English also used colon for the anatomical section of the large intestine through a separate medical line from Greek and Latin. Modern English therefore carries two related but distinct uses under one spelling. In both, the old idea is the same: a part within a larger body.