Glyph

Various glyphs representing lower case letter ⟨a⟩ in various typefaces and as single- and double-storey; they are allographs of the same grapheme

A glyph (/ɡlɪf/ GLIF) is any kind of purposeful mark. In typography, a glyph is "the specific shape, design, or representation of a character". It is a particular graphical representation, in a particular typeface (or computer font), of an element of written language. That "element" is called a grapheme – the conceptual abstraction of some letter, number or symbol, which is independent of the glyph designed to represent it in a particular font.