المعنى الاصطلاحي :

The first four Caliphs, who successively ruled the Muslims after the death of the Prophet, may Allah's peace and blessings be upon him.

الشرح المختصر :

"Al-Khulafā’ Ar-Rāshidīn" (the Rightly-Guided Caliphs): The best of nations is the nation of Muhammad, may Allah's peace and blessings be upon him; and the best of this nation, after its Prophet are the four Rightly-Guided Caliphs, who are: Abu Bakr, ‘Umar, ‘Uthmān, and ‘Ali, may Allah be pleased with them. They were the ones who accompanied the Prophet, may Allah's peace and blessings be upon him, right from the beginning of Islam, then they were assigned the caliphate and leadership after the death of the Prophet, may Allah's peace and blessings be upon him, to look after the believers' affairs by establishing the religion and protecting the Muslims in such a way that it was obligatory for all people to follow them, and it was not permissible to oppose them. The total period of their rulership was thirty years. The caliphate of Abu Bakr as-Siddiq was two years and three months, the caliphate of ‘Umar was ten years and a half, the caliphate of ‘Uthmān was twelve years, and the caliphate of ‘Ali was four years and nine months. The belief of Ahl-us-Sunnah (the followers of the Sunnah) is that their ranking of merit is the same as their order in the caliphate.