council, an assembly = (majlis) مَجْلِس

Plural: مَجَالِس
Associated verb: to sit جَلَسَ (يَجْلِسُ) – جُلُوْسًا

Examples

يَا أَيّهَا الّذِينَ آمَنُوا إِذَا قِيلَ لَكُمْ تَفَسّحُوا فِي الْمَجَالِسِ فَافْسَحُوا يَفْسَحِ اللَّهُ لَكُمْ O ye who believe! When ye are told to make room in the assemblies, (spread out and) make room: (ample) room will God provide for you – Quran, 58:11

عَنْ أَبِي مُوسَى ، أَنّ رَسُولَ الله صَلّى الله عَلَيْهِ وَسَلّمَ قَالَ : إِذا مَرّ أَحَدُكُمْ فِي مَجْلِسٍ أَوْ سُوقٍ ، وَبِيَدِهِ نَبْلٌ ، فَلْيَأْخُذْ بِنِصالِهَا ، ثُمّ لِيَأْخُذْ بِنِصالِهَا ، ثُمّ لِيَأْخُذْ بِنِصالِهَا On the authority of Abu Musa, that the Prophet, God bless him and grant him peace, said, “When one of you passes through an assembly (of people) or a market, and he is holding arrows, let him grasp them by their arrow-head, again let him grasp them by their arrow-head, again let him grasp them by their arrow-head” – Muslim

حَلّ مَجْلِسُ الوُزَرَاءِ الْبَاكِسْتَانِيّ بَعْدَ الْحُكْمِ بِعَدَمِ أَهْلِيّةِ رَئِيْسِهِ The Pakistani cabinet (lit. the council of ministers) has been dissolved following the judgement against the eligibility of its Prime Minister – BBC News, Arabic

Did you know…

مَجْلِس is an example of a noun of place and time, which are formed by taking the root letters of a verb (in this case جلس ), and putting them on the morphological template مَفْعَل or مَفْعِل . So literally مَجْلِس means the the sitting-place. By extension (in this, case, synendoche, which is a type of figure of speech which, amongst other things, can be used to refer to the contents of a thing by their container, e.g. “would you like a cup”, where “cup” is being used for “cup of tea”), it can also mean the people, or the gathering, at a particular sitting place, and hence an assembly.