R
- Rabb (ربّ)
- Lord, Sustainer, Cherisher, Master.
- R. A., Radiyallahu anhu
- May Allah be pleased with him. Variants are anha (her) and anhum (them).
- Rahman (رحمن)
- Merciful; Ar-Rahman (الرحمن) means "The Most Merciful"
- Rahim (رحيم)
- compassionate; Ar-Rahim (الرحيم) means "The Most Compassionate" as in the Basmala
- Rajm (رجم)
- the practice of stoning
- Raka'ah
- one unit of Islamic prayer, or Salat. Each daily prayer is made up of a different number of raka'ah.
- Ramadhan
- month of fasting when the Qur'an was first revealed
- Rashidun
- Sunnis consider the first four caliphs as the "orthodox" or "rightly guided" caliphs. They were Abu Bakr, 'Umar, 'Uthman and 'Ali.
- Rasul (رسول)
- messenger; Unlike prophets (Nabi), messengers are given scripture. Moses, David, Jesus and Mohammed are considered messengers. All messengers are considered prophets, but not all prophets are given scripture. See: Nabi.
- Riba (ربا)
- interest, the charging and paying of which is forbidden by the Qur'an
- Ribat
- Guarding Muslims from infidels
- Riddah (ردة)
- apostasy, in which a person abandons Islam for another faith or no faith at all.
- Risalah (رِسَالَة)
- literally, message or letter. Used both in common parlance for mail correspondences, and in religious context as divine message.
- Ruh (روح)
- spirit; the divine breath which God blew into the clay of Adam.
- Rukn plural arkan
- means what is inevitable. One of the five pillars of Islam. (See fard, wajib)
- Ruk'u
- the bowing performed during salat.
Read more about this topic: Glossary Of Islam