What term describes a written symbol with no meaning?

The term that accurately describes a written symbol with no meaning is a grapheme. A grapheme refers to the smallest unit of a writing system and can represent individual sounds (phonemes) in a language. While a graph typically represents data in a visual format, it does not specifically denote a written symbol with no intrinsic meaning. Therefore, the consideration for grapheme allows a clearer understanding of individual symbols that may not necessarily convey meaning on their own but function within a writing system.

Orthography, on the other hand, pertains to the conventional spelling system of a language, including rules and patterns for how language is represented in written form. Allographs refer to different representations of the same grapheme, such as a letter written in various cases (e.g., 'a' and 'A'). Hence, the most accurate term for a written symbol devoid of meaning is grapheme, emphasizing its role within the broader context of phonetics and linguistics.