اسم المصدر- “ism al-maṣdar”

Definition: usually refers to the effect or the result of a corresponding maṣdar, like in حب (love) which is a result of محبة (to love or to affect) or بغض (hatred) which is a result of بغاضة (to hate), or غُسل (cleanliness) which is a result of غَسل (to clean). More precisely however, it is defined by not having the letters most common for that particular verb, like حبّ which corresponds to the verb أحبّ.