MHD CLASSIFICATION SYSTEM
(based on MHD Reference Materials 1: Preliminary Revised Glyph Catalog. Glyph Dwellers report #71, Jan. 2022)
(Original version in Table 4 of: Macri, M. and Looper, M., The New Catalog of Maya Hieroglyphs, Volume One: The Classic Period Inscriptions. Norman: University of Oklahoma Press, 2003. Available only in print.)

Note: The third character is arbitrarily assigned 1,2,..,9,A,..,F. In some cases a fourth character is added, which is an arbitrary lowercase letter a,b,c,... except that "s" is reserved for glyph forms that are used only for syllables (syllabograms). (However, some syllabograms have just regular three-character or a,b,c,... part naming.) If the glyph form can occur as both a logogram and a syllabogram, then the suffix may be, for example, a/s. Note also that not only the first, but also the second letter is often mnemonic, reflecting usually the first letter of the English -- or sometimes, for lack of letters, Spanish (indicated below in italics) -- description for the subclass they represent.