logogram

n. symbol that stands for an entire word (such as "&" in place of "and")

A logogram, or logograph, is a single grapheme which represents a word or a morpheme (a meaningful unit of language). This stands in contrast to other writing systems, such as syllabaries, abugidas, abjads, and alphabets, where each symbol (letter) primarily represents a sound or a combination of sounds.
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Noun
1. a single written symbol that represents an entire word or phrase without indicating its pronunciation; "7 is a logogram that is pronounced `seven' in English and `nanatsu' in Japanese"
(synonym) logograph
(hypernym) ideogram, ideograph

n. logogram

(n.)
A word letter; a phonogram, that, for the sake of brevity, represents a word; as,