Quadriliteral verbs in Arabic (الأَفْعال الرُباعية), possess four letters in their root (the pattern فَعْلَلَ) differentiating them from the typical triliteral verb. They are conjugated similarly to form II (فَعَّلَ) of the triliteral verb and have 3 augmented forms. Several quadriliteral verbs (فَعْلَلَ) are formed from a doubled biliteral syllable, giving an onomatopoeic effect. They can also be constructed from words borrowed from other languages.

Augmented forms / الأَوْزان المَزيدة

There are 3 augmented forms (الأَوْزان المَزيدة), only two of which are still used:

• Form II (تَفَعْلَلَ) is the reflexive-passive of form I and is conjugated like form V of triliteral verbs (الفِعْل الثُلاثيّ):

• Form IV (اِفْعَلَلَّ) is conjugated like form X of triliteral verbs having a doubled root letter (الفِعْل المُضاعَف). Very few verbs are actually built with this form.

• Note: Form III (اِفْعَنْلَلَ) is only included here for reference since it has almost disappeared.

المَصْدَر Verbal noun	اِسْمُ المَفْعُول Passive Participle (recipient)	اِسْمُ الفاعِل Active Participle (agent)	الأَمْر Imperative	المُضارِع Imperfect (present)	الماضي Perfect (past)	الوَزْن Form	المَعْنى Meaning
اِفْعِنْلَالٌ	مُفْعَنْلَلٌ	مُفْعَنْلِلٌ	اِفْعَنْلِلْ	يَفْعَنْلِلُ	اِفْعَنْلَلَ	III	(default pattern)
اِحْرِنْجامٌ	مُحْرَنْجَمٌ	مُحْرَنْجِمٌ	حْرَنْجِمْ	يَحْرَنْجِمُ	اِحْرَنْجَمَ		To foregather