The Collaborative International Dictionary of English v.0.48:

Glyph \Glyph\ (gl[i^]f), n. [Gr. glyfh` carving, fr. gly`fein to
   carve: cf. F. glyphe. Cf. Cleave to split.]
   1. (Arch.) A sunken channel or groove, usually vertical. See
      Triglyph.
      [1913 Webster]

   2. (Arch[ae]ol.) A carved figure or character, incised or in
      relief; a carved pictograph; hence, a pictograph
      representing a form originally adopted for sculpture,
      whether carved or painted.
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

glyph
    n 1: glyptic art in the form of a symbolic figure carved or
         incised in relief

Moby Thesaurus II by Grady Ward, 1.0:

21 Moby Thesaurus words for "glyph":
   anaglyph, bas-relief, boss, cameo, cameo glass, cavo-rilievo,
   cut glass, embossment, glyptograph, high relief, intaglio,
   intaglio rilevato, intaglio rilievo, low relief, mask, medal,
   medallion, plaquette, relief, relievo, sculptured glass



The Free On-line Dictionary of Computing (30 December 2018):

glyph

    An image used in the visual representation of
   characters; roughly speaking, how a character looks.  A
   font is a set of glyphs.

   In the simple case, for a given font (typeface and size),
   each character corresponds to a single glyph but this is not
   always the case, especially in a language with a large
   alphabet where one character may correspond to several glyphs
   or several characters to one glyph (a character encoding).

   Usually used in reference to outline fonts, in particular
   TrueType.

   (1998-05-31)