In Classical and Modern Standard Arabic, nouns, pronouns, adjectives, and verbs are morphologically marked for number. Three categories of number are recognized by both medieval and modern grammarians: singular (mufrad), dual (mut̲annā), and plural (jamʿ). The singular in general refers to a single item in a class, the dual to two items of a class, the plural to three or more. An important exception to this generalization is that for a small set of nouns, termed ‘collectives’, the unmarked singular form refers to a collection or group, and a singulative (ism al-waḥda lit. ‘noun of the…