The word(s) "idea" appears 3 time(s) in 3 verse(s) in Quran in Abdullah Yusuf Ali translation.

(1) And on them did Satan prove true his idea, and they followed him, all but a party that believed.

(سورة سبإ, Saba, Chapter #34, Verse #20)
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(2) "Then what is your idea about the Lord of the worlds?"

(سورة الصافات, As-Saaffaat, Chapter #37, Verse #87)
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(3) "And when it was said that the promise of Allah was true, and that the Hour- there was no doubt about its (coming), ye used to say, 'We know not what is the hour: we only think it is an idea, and we have no firm assurance.'"

(سورة الجاثية, Al-Jaathiya, Chapter #45, Verse #32)
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