A Glossary of Old Syrian: ʔ – ḳ is the first of two volumes aimed at the completion of a lexicographical index of the Old Syrian linguistical continuum. This glossary gives a picture, or map, of the Old Syrian lexicon as it can be extracted and reconstructed from the available sources, from the (Old Akkadian-)Eblatic through the Old and Middle Babylonian corpora. Old Syrian can be defined most appropriately as a diachronically conservative, geographically pluricentric, and pragmatically multilayered linguistic cluster. Therefore, the present work pays special attention to the distribution of lexical data along diatopic and diastratic criteria. In view of the enormous amount of material and the dispersion of the data, this glossary focuses on the most representative textual corpora of the Old Syrian linguistic landscape. The bibliographical references are kept deliberately succinct and as a rule, restricted to the classic works that may be easily found in every Assyriological or Semitic library, public or private, and that will redirect the users to their sources. Since the Old Syrian lexicography remains uncertain, the leading interpretative opinions are included alongside the most relevant comparative Semitic material. A Glossary of Old Syrian offers a clear picture of the current state of this field and is intended to serve as a reference work in support of future study.