Grammar term · Sarf · morphology
نَاقِص
naqis
Defective root (weak final)
Sarf · morphologyRoot soundness (sihha/i'lal)core term2,860+ in the Qur'an
In one line
The weak-tailed root: a weak final radical — دَعَا (دعو), رَمَى (رمي) — whose ending bends and drops through the conjugation.
Classical definition
النَّاقِصُ مَا كَانَتْ لَامُهُ حَرْفَ عِلَّةٍ، كَدَعَا وَرَمَى.
“The naqis is that whose final radical is a weak letter, like da'a and rama.”
(بتصرف من شذا العرف)
Key words in the Arabic
لَامُهُits final radical
نَاقِصdeficient — weak at the end
Understand it
With the weakness at the tail, every ending negotiates with it: the weak letter flips to alif in the madi (دَعَا), hides the damma and kasra in the mudari' (يَدْعُو، يَرْمِي — i'rab muqaddar), and drops clean off in jazm and the amr: لَمْ يَدْعُ، ٱدْعُ. The dropped-letter jazm is one of the Qur'an's most common sights: فَلَا تَخْشَوُا۟... لَمْ يَخْشَ.
How to spot it
Recognition test
Dictionary form ends in ى or ا (root و/ي): naqis. In jazm or amr, the missing final letter IS the marker — say 'jazm shown by deletion of the weak letter'.
In the Qur'an
فَدَعَا رَبَّهُۥٓ أَنِّى مَغْلُوبٌ فَٱنتَصِرْ
Al-Qamar 54:10 — “So he called upon his Lord: I am overpowered, so help”
دَعَا — root دعو: the final waw flipped to alif; in the amr it vanishes altogether (ٱدْعُ).
Forms it takes
ناقص يائييائيناقص واويواوي
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