Definition - A character that symbolizes the idea of a thing, but which gives no indication of how it should be pronounced.

1. They are also called ideograms.

Example -
@, #, $, %, &, 2, 9, and 0

Etymology -
The word derives from the Greek idea, form + graphe, writing.

Oxford English Dictionary -
The term's first citation is from 1835–40:
"Hieroglyphic characters are either ideographs, that is, representations of ideas, or phonographs, that is, representations of sounds."
(Hincks On Hieroglyphics (MS. B.M., Egypt. Antiq., 19 e),)

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