Tafsir of Ash-Shu`ara' 26:198

"And if We had sent it down" — meaning the Qur’an, with its elegant and miraculous structure — "upon some of the non-Arabs (al-a‘jamiīn)," who are unable to speak in Arabic. It is the plural of a‘jamī, as stated in al-Taḥrīr and other works, except that the relational yā’ (ya’ al-nasab) has been elided for the sake of brevity. Similar to this is al-ash‘arīn, the plural of ash‘arī, as in the verse by al-Kumayt:

If I had prepared a fleeing rhyme, it would have entered the houses of the Ash‘arīs.

Al-Ḥasan and Ibn Muqsim read it with the relational yā’ according to the original form. Ibn ‘Aṭiyyah said: "It is the plural of a‘jam, which refers to one who does not speak clearly, even if he is of Arab lineage. The ‘ajamī is one whose lineage is in the ‘Ajam (non-Arab lands), as opposed to the Arabs, even if he were the most eloquent of people." This concludes his statement.

It has been objected that the feminine of a‘jam is ‘ajmā’, and the af‘al-fa‘lā’ pattern does not form a sound masculine plural. This was answered by the assertion that al-a‘jam originally refers to the dumb animal (al-bahīmah al-‘ajmā’) due to its inability to speak, and was later transferred or used metaphorically for the aforementioned meaning. In that sense, it has no feminine of the fa‘lā’ pattern, and thus it is pluralized with the sound masculine plural. This was countered by the observation that the scholar Muḥammad ibn Abī Bakr al-Rāzī explicitly stated in his book Gharā’ib al-Qur’ān that al-a‘jam is one who does not speak clearly, and the feminine is ‘ajmā’. Even if one concedes that it lacks a feminine form in that specific meaning, the principle is to observe its origin. To this, it is said that the removal of an impediment due to a specific circumstance is a recognized permit among the grammarians. Furthermore, the rule that af‘al-fa‘lā’ does not form a sound masculine plural is the position of the Basrans, whereas al-Farrā’ and other Kufans permit it; thus, perhaps those who claimed it is the plural of a‘jam did so based on that view. The nature of the aforementioned plural suggests that the intended meaning refers to rational beings. Some have suggested it is the plural of a‘jam referring to non-rational beasts, and it was pluralized as a rational plural because it was described as being sent down upon them.