Three types of nouns show declension irregularities:
- Shortened nouns
- Extended nouns
- Defective nouns
I. Shortened nouns
A shortened noun اِسْمٌ مَقْصُوْرٌ is a noun whose singular stem ends with a shortened ʔalif, that is, it ends with either –ȃ ـــَــا or –a·y ـــَــى , which are pronounced the same.
The weak ʔalif at the end of a shortened noun stem is always altered from a consonant, which can be either w و or y ي , depending on the written shape of the ʔalif. If it is written ا , the original consonant is w. If it is written ى , the original consonant is y.
In words with more than three letters, the terminal ʔalif will be always written ى if the letter preceding it is not ي , and will be written ا otherwise.
Inflection and derivation often requires restoring the original consonant lying behind the terminal weak ʔalif, which should be easy if you can see the written form of the word.
If the shortened noun is triliteral, the altered consonant of the weak ʔalif is always considered to be a radical (root consonant). If the shortened noun has more than three letters, the altered consonant may be a radical or may be part of a suffix –ȃ/–a·y, depending on the structure of the word. The suffix –ȃ/–a·y is usually diptotic and serves either as a feminine marker in a singular feminine noun or an augmentative marker in a broken plural structure.
Following are examples of shortened nouns. The radicals are colored blue.
|the stick (fem.)||ʔ·al-ʕaṣaa||اَلْعَصَاْ|
|the dew (masc.)||ʔ·an-nada·y||اَلْنَّدَىْ|
|the forces (plur. fem.)||ʔ·al-qiwa·y||اَلْقِوَىْ|
|the dock (masc.)||ʔ·al-marsa·y||اَلْمَرْسَىْ|
|the lowest/nearest (fem.)||ʔ·ad-dunyȃ||اَلْدُّنْيَاْ|
|the wounded (plur. fem.)||ʔ·al-ǵarħa·y||اَلْجَرْحَىْ|
|the hospital (masc.)||ʔ·al-mustašfa·y||اَلْمُسْتَشْفَىْ|
II. Extended nouns
An extended noun اِسْمٌ مَمْدُودٌ is a noun whose singular stem ends with –ȃʔ ـــَــاء .
The terminal hamza·t of an extended noun stem can be original or altered from w و or y ي . There is no way to tell which is the case without looking in a dictionary.
If the extended noun is triliteral, the terminal hamza·t is a radical. If the noun has more than three letters, the hamza·t may be a radical or may be part of a suffix –ȃʔ ـــَــاء . This suffix is usually diptotic and serves either as a feminine marker in a singular feminine noun or an augmentative marker in a broken plural structure.
Following are examples of extended nouns. The radicals are colored blue.
|a heaven (fem.)||samȃʔuṋ||سَمَاْءٌ|
|a supper (masc.)||ʕašȃʔuṋ||عَشَاْءٌ|
|a desert (fem.)||ṣaħrȃʔu||صَحْرَاْءُ|
|friends (plu. masc.)||ʔaṣdiqȃʔu||أَصْدِقَاْءُ|
III. Defective nouns
A defective noun اِسْمٌ مَنْقُوصٌ is a noun whose singular stem ends with –ȋ ــِــيْ .
The final y ي of a defective noun is usually a radical, either original or altered from w و . However, the ending –ȋ is a diptotic suffix in the broken plural structure ʔ·al-faʕȃlȋ الْفَعَالِي (a diptotic feminine suffix –ȋ exists only vestigially in Classical Arabic). A suffix –ȋ also exists in Classical Arabic as a variant of the nisba⋅t suffix –iyy ــِـيّ .
|the judge (masc.)||ʔ·al-qȃḍiy||اَلْقَاْضِيْ|
|the sponsor (masc.)||ʔ·ar-rȃʕiy||اَلْرَّاْعِيْ|
|the attorney (masc.)||ʔ·al-muħȃmiy||اَلْمُحَاْمِيْ|
|the snakes (plu. fem.)||ʔ·al-ʔafȃʕiy||اَلْأَفَاْعِيْ|
|the nights (plu. fem.)||ʔ·al-layȃliy||اَلْلَّيَاْلِيْ|
|the Yemeni (masc.)||ʔ·al-yamȃniy||اَلْيَمَاْنِيْ|