Morphemes combined with the Arabic noun are clearly described in the literature, but their interpretation can be somewhat nebulous, and a unified scholarly analysis does not as yet exist. This book proposes a new and unified perspective regarding these morphemes, analyzing them as copulae, and the constructions in which they occur as instances of predication.Analyzing morphemes combined with the Arabic noun as copulae explains many of their puzzling properties (rise and loss of declension, proteiform nature of nunation, etc.). Emphasis is placed on data previously marginalized in the description of these morphemes, from pre-Classical Arabic transmitted by Arab Grammarians, Semitic languages that contributed to the emergence of Arabic through language contact, and roughly 30 languages genetically unrelated to Arabic.