Grammar term · I'rab · i'rab
عَلَامَة الْبِنَاء (الْحَرَكَة)
'alamat al-bina' (al-haraka)
Build-vowel (mabni 'ala fath/damm/kasr)
I'rab · i'rabDeclinability (bina)core term31,396+ in the Qur'an
In one line
The fixed vowel a mabni word is “built on” — described as mabni 'ala al-fath, al-damm or al-kasr.
Understand it
When an analysis says حَيْثُ is “built on damm” or أَيْنَ “built on fath”, it names the vowel that permanently ends the word. It looks like an i'rab marker but is not one: no governor caused it and none can change it. The phrase مَبْنِيٌّ عَلَى الْفَتْحِ in i'rab is simply the formal way of recording that fixed vowel.
How to spot it
Recognition test
The same final vowel in every sentence, whatever the word's job — a build-vowel, not i'rab.
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