Rabb-Ul-Maal: The one who provides the finance in a Mudhaarabah agreement.

Rabi-al-Awwal: The third month of the Islamic calendar.

Radiallahu-Anha: May Allah be pleased with her.

Rajih: Preferable.

Rak'at: One unit of a prayer.

Ramadhaan: Ninth month of the Islamic calendar.

Rasool: A messenger.

Rasulullah: Messenger of Allah (Prophet Muhammad).

Ratl: A measure used in Baghdad to weigh foodstuffs.

Riba: Literally means increase or addition and refers to the 'premium' that must be paid by the borrower to the lender along with the principal amount as a condition for the loaner OR an extension in its maturity. It is equivalent to interest.

Rikaaz: Buried treasure.

Rooh: Soul.

Rub-ul-Ushr: Quarter of a tenth.

Ruku: Ritual of bowing down in prayer.

Rukun: A principle.

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