Abecedarius is a rare and ancient word that means a work that is arranged alphabetically. Although there are not many synonyms for this term, some possible options include alphabetical, lexicon, glossary, and index. These words also refer to materials that are arranged in alphabetical order, making them useful for finding specific information quickly and easily. Additionally, terms such as dictionary, encyclopedia, and reference work can also be considered synonyms for abecedarius, as they often feature alphabetical organization and serve as comprehensive sources of information. Regardless of the specific word used, the concept of alphabetically organizing information has been a valuable tool for academics, writers, and researchers throughout history.