What is another word for "letter"?

Roget's Thesaurus (1911) lists these synonyms for "letter": abecedarian, abecedary, abuse, accent, account, accredit, affix, all, alphabet, alphabetical, ambassador, ambiguity, amusement, anagram, anagrammatism, anastatic, and, anniversary, antiphrasis, apparitor, aquatint, aquatinta, arch, archaic, archaism, argot, artillery, autotype, babu, bag, barbarism, bearer, bellman, billet, billet-doux, bite, black, block, bonfire, boy.