1. Definition
The fāʿil (lit. ‘he who does’) corresponds, in the analysis of the Arab grammarians, to the protagonist of the verb. It is the primary element to which the verb relates (Sībawayhi, Kitāb I, 33–34), meaning that the verb “does not go without it” (Sīrāfī, Šarḥ II, 267). In fact, the verb (fiʿl) and its fāʿil constitute a pair “each of whose two elements cannot go without the other, and which the speaker cannot do without” (lā yaġnā wāḥidun min-humā ʿan …