The word(s) "grey" appears 3 time(s) in 3 verse(s) in Quran in Mohsin Khan translation.

(1) He said: "My Lord! Indeed my bones have grown feeble, and grey hair has spread on my head, And I have never been unblest in my invocation to You, O my Lord!

(سورة مريم, Maryam, Chapter #19, Verse #4)
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(2) Allah is He Who created you in (a state of) weakness, then gave you strength after weakness, then after strength gave (you) weakness and grey hair. He creates what He wills. And it is He Who is the All-Knowing, the All-Powerful (i.e. Able to do all things).

(سورة الروم, Ar-Room, Chapter #30, Verse #54)
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(3) Then how can you avoid the punishment, if you disbelieve, on a Day (i.e. the Day of Resurrection) that will make the children grey-headed?

(سورة المزمل, Al-Muzzammil, Chapter #73, Verse #17)
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