Al Azif is the original Arabic title of the Necronomicon, naming the nocturnal cry of insects — the sound the ancients took for the howling of demons. It is the name of the first version, written by Abdul Alhazred.
Its etymology, of something unhearable leaking out as sound, resonates with the Pnakotic Press motto "that which does not sound is heard" (AUDITUR QUOD NON SONAT).