Grammar term · Nahw · syntax
حَرْف رَدْع
harf rad'
Deterrence particle (rad')
Nahw · syntaxParticle typeadvanced term33+ in the Qur'an
In one line
The deterrence particle — كَلَّا: “By no means!”, slamming the door on what was just said.
Classical definition
كَلَّا حَرْفُ رَدْعٍ وَزَجْرٍ يُفِيدُ النَّهْيَ عَنْ قَوْلٍ أَوْ فِعْلٍ سَابِقٍ.
“Kalla is a particle of rebuke and deterrence, conveying prohibition of a preceding word or deed.”
(بتصرف من ابن هشام)
Key words in the Arabic
رَدْع وَزَجْرrebuke and deterrence
Understand it
كَلَّا rejects what came before it — a claim, a hope, an excuse — and often pivots the passage: كَلَّا سَيَعْلَمُونَ, “No indeed — they will come to know”. In later suras it fires like a hammer-blow; some readings treat certain occurrences as “truly” (softened emphasis), which is why translations of the same كَلَّا differ.
How to spot it
Recognition test
كَلَّا at a clause break — rejection of what precedes, warning in what follows.
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