The word(s) "unfathomable" appears 1 time(s) in 1 verse(s) in Quran in Saheeh International translation.

(1) Or [they are] like darknesses within an unfathomable sea which is covered by waves, upon which are waves, over which are clouds - darknesses, some of them upon others. When one puts out his hand [therein], he can hardly see it. And he to whom Allah has not granted light - for him there is no light.