The word(s) "foolishness" appears 3 time(s) in 3 verse(s) in Quran in Saheeh International translation.

(1) Those will have lost who killed their children in foolishness without knowledge and prohibited what Allah had provided for them, inventing untruth about Allah. They have gone astray and were not [rightly] guided.

(سورة الأنعام, Al-An'aam, Chapter #6, Verse #140)
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(2) Said the eminent ones who disbelieved among his people, "Indeed, we see you in foolishness, and indeed, we think you are of the liars."

(سورة الأعراف, Al-A'raaf, Chapter #7, Verse #66)
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(3) [Hud] said, "O my people, there is not foolishness in me, but I am a messenger from the Lord of the worlds."

(سورة الأعراف, Al-A'raaf, Chapter #7, Verse #67)
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