The word(s) "decisive" appears 4 time(s) in 4 verse(s) in Quran in Saheeh International translation.

(1) Then judge between me and them with decisive judgement and save me and those with me of the believers."

(سورة الشعراء, Ash-Shu'araa, Chapter #26, Verse #118)
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(2) Or have they other deities who have ordained for them a religion to which Allah has not consented? But if not for the decisive word, it would have been concluded between them. And indeed, the wrongdoers will have a painful punishment.

(سورة الشورى, Ash-Shura, Chapter #42, Verse #21)
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(3) I wish my death had been the decisive one.

(سورة الحاقة, Al-Haaqqa, Chapter #69, Verse #27)
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(4) Indeed, the Qur'an is a decisive statement,

(سورة الطارق, At-Taariq, Chapter #86, Verse #13)
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