A horizontal line used by the Greeks to show that a new topic was being introduced.

Etymology -
The word derives from the Greek paragraphos, from para, beside, and graphein, to write; thus "that which is written beside."

Example Usages -

1. "In the oldest Greek literary texts, written on papyrus during the 4th century bc, a horizontal line called the paragraphos was placed under the beginning of a line in which a new topic was introduced. This is the only form of punctuation mentioned by Aristotle."
(Source: )

2. "…a short horizontal stroke drawn below the beginning of a line in which a break in the sense occurs…"
(Source: OED s.v. paragraph )

3. "Writing in ancient Greece was broken by neither marks nor spaces. Lines of closely-packed letters ran left to right across the page and back again like a farmer ploughing a field. The sole aid to the reader was the paragraphos, a simple horizontal stroke in the margin that indicated something of interest on the corresponding line. It was up to the reader to work out what, exactly, had been highlighted in this fashion: a change of topic, perhaps; a new stanza in a poem; or a change in speaker in a drama."
(Source: Shady Characters: The secret life of punctuation (Maximal meaning in minimal space: the history of punctuation) )

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