Grammar term · The ism · Definiteness

What is a relative clause (silat al-mawsul)?

silat al-mawsul
صِلَة الْمَوْصُول
The ismDefinitenesscore term
Also written: Sila · Silat al mawsul · Relative clause · The connector clause
In one line
The relative clause is the sentence that completes a relative noun — it says who “the one who…” actually is, and holds no place in i'rab.
Definition and ruling
صِلَةُ الْمَوْصُولِ لَا مَحَلَّ لَهَا مِنَ الْإِعْرَابِ، وَهِيَ نَوْعَانِ: جُمْلَةٌ وَشِبْهُ جُمْلَةٍ.
“The relative clause holds no position in i'rab. It is of two kinds: a full sentence, or a semi-sentence.”
(النحو التطبيقي)
Key words in the Arabic
لَا مَحَلَّ لَهَا مِنَ الْإِعْرَابِholds no i'rab position
شِبْهُ جُمْلَةٍa semi-sentence — an adverb, or a preposition with its noun
Understand it

Say جَاءَ الَّذِي and everyone waits: who came? The sila answers — جَاءَ الَّذِي أَكْرَمْتُهُ — and the pin's word for that is removing the ibham built into every mawsul. Inside the sila lives a rabit, a pronoun stated or hidden that reaches back to the mawsul: the ـهُ of أَكْرَمْتُهُ. However long the sila runs, as a block it has no mahall; the mawsul itself carries the i'rab in the main sentence.

How to spot it
Recognition test
Find the mawsul (الَّذِي، الَّتِي، مَنْ، مَا…), then bracket everything needed to complete 'the one who…' — that bracket is the sila. Check it contains its returning pronoun.
In the Qur'an
قَدْ سَمِعَ ٱللَّهُ قَوْلَ ٱلَّتِى تُجَٰدِلُكَ فِى زَوْجِهَا وَتَشْتَكِىٓ إِلَى ٱللَّهِ وَٱللَّهُ يَسْمَعُ تَحَاوُرَكُمَآ ۚ إِنَّ ٱللَّهَ سَمِيعٌۢ بَصِيرٌ
Al-Mujadila 58:1 — “Allah has indeed heard (and accepted) the statement of the woman who pleads with thee concerning her husband and carries her complaint (in prayer) to Allah: and Allah (always) hears the arguments between both sides among you: for Allah hears and sees (all things).”
تُجَٰدِلُكَ is the sila of ٱلَّتِى — its hidden هِيَ is the rabit — and the clause takes no i'rab place.
In the language — فِي اللُّغَة

The word صِلَة (ṣila) in everyday Arabic means a link, a bond, a keeping of ties.

صِلَةُ الرَّحِمِ (ṣilatu al-raḥim) — “keeping the ties of kinship”

As a grammatical term it means the clause that links onto a relative noun and completes it.

Common questions

Why does the relative clause have no place in i'rab?

Because it is not filling a role — it is completing a word. The relative noun is the part that takes the i'rab; the clause after it only says who or what that noun refers to. There is no slot for it to occupy.

Next in the guideالْمُنَادَىWhat is a vocative noun (munada)? →

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