Grammar term · Sarf · morphology
حَذْف التَّاء لِلتَّخْفِيف
hadhf al-ta' li-l-takhfif
Ta-deletion for ease
Sarf · morphologyMorphophonemic processadvanced term58+ in the Qur'an
In one line
The vanishing ta: when a mudari' would begin تَتَـ, one ta may drop for lightness — تَتَنَزَّلُ reads تَنَزَّلُ.
Classical rule
قَدْ تُحْذَفُ إِحْدَى التَّاءَيْنِ مِنَ المُضَارِعِ المَبْدُوءِ بِتَاءَيْنِ تَخْفِيفًا، كَتَذَكَّرُونَ أَصْلُهَا تَتَذَكَّرُونَ.
“One of the two tas may be deleted, for lightness, from a present-tense verb beginning with two tas.”
(بتصرف من شذا العرف)
Key words in the Arabic
إِحْدَى التَّاءَيْنِone of the two tas
تَخْفِيفًاfor lightness
Understand it
Forms V and VI (تَفَعَّلَ، تَفَاعَلَ) begin with ta; add the mudari' prefix تَـ for 'you' or 'she' and the word stutters: تَتَنَزَّلُ، تَتَذَكَّرُونَ. The Qur'an frequently drops one ta — تَنَزَّلُ ٱلْمَلَٰٓئِكَةُ, لَعَلَّكُمْ تَذَكَّرُونَ — and the reader must supply it mentally to parse the form correctly: تَنَزَّلُ is Form V mudari', not a madi. Context and the fatha-pattern give it away.
How to spot it
Recognition test
A mudari'-looking verb from Forms V/VI with only one ta where sense demands 'she/you/they-fem': assume the twin ta dropped. Test by restoring it — if تَتَـ fits the meaning, that is the asl.
In the Qur'an
تَنَزَّلُ ٱلْمَلَٰٓئِكَةُ وَٱلرُّوحُ فِيهَا
Al-Qadr 97:4 — “The angels and the Spirit descend in it”
تَنَزَّلُ is تَتَنَزَّلُ with one ta dropped for lightness — Form V mudari', not a madi.
Forms it takes
وفيه حذف إحدى التاءين من المضارع للتخفيف
Related terms