Overview
A character is a semiotic sign or symbol, or a glyph typically a letter, a numerical digit, an ideogram, a hieroglyph, a punctuation mark or another typographic mark.
History
The Ancient Greek word ('charaktēr') is an agent noun of the verb (charassō) with a meaning "to sharpen, to whet", and also "to make cake", from a PIE root "cut" also continued in Irish gearr and English gash, which is perhaps an early loan ultimately from the same Greek root.
A is thus an "engraver", originally in the sense of a craftsman, but then also used for a tool used for engraving, and for a stamp for minting coins. From the stamp, the meaning was extended to the stamp impression, Plato using the noun in the sense of "engraved mark". In Plutarch, the word could refer to a figure or letter, Lucian uses it of hieroglyphs as opposed to Greek grammata (Herm. 44)
Metaphorically, it could refer to a distinctive mark, Herodotus (1.57) using it of a particular dialect, or (1.116) of a characteristic mark of an individual. The collective noun "characteristics" appears later, in Dionysius Halicarnassensis.
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