Mubīn — Clear / Clarifying
Summary: Ism fāʿil and ism mafʿūl of أَبَانَ (Form IV) that look identical on the surface due to the ajwaf root — context determines which meaning is intended. (source: surah_yusuf_session2.md)
Root and Base Verb
Root: ب-ي-ن — note the yāʾ turns into an alif in the māḍī (weak letter / ajwaf rule).
| Form | Word | Meaning |
|---|---|---|
| Māḍī (root verb) | بَانَ | something becomes clear (intransitive) |
| Muḍāriʿ | يَبِينُ | becomes clear |
| Form IV māḍī | أَبَانَ | to clarify something (transitive — passes to an object) |
| Maṣdar | بَيَان | the process/act of clarifying |
| Ism fāʿil / mafʿūl | مُبِين | clarifying / clarified |
Note on بَيَان: the wāw/yāʾ of the root + tāʾ of Form VIII merge, producing بَيَان rather than the expected اِبتيان. (source: surah_yusuf_session2.md)
Why Ism Fāʿil and Ism Mafʿūl Look Identical
Form IV ism fāʿil pattern: مُفْعِل; ism mafʿūl pattern: مُفْعَل. For أَبَانَ (an ajwaf/hollow verb), both surface forms converge through different phonological paths: (source: surah_yusuf_session2.md)
Ism Fāʿil
مُبَيِّن → kasra and yāʾ are phonetically incompatible → shift → مُبِين
Ism Mafʿūl
مُبَيَّن → fatḥa moves to bāʾ → مُبَان → further smooths → مُبَون → مُبِين
Result: Both look identical — مُبِين. Context determines meaning: - Ism fāʿil: the one clarifying (active) - Ism mafʿūl: the thing that was clarified (passive)
This is a surface ambiguity arising from the phonological rules that govern ajwaf verbs — not an irregularity.