Muhajir or Mohajir (Arabic: مهاجر) is an Arabic word meaning refugee or immigrant or emigrant. The Islamic calendar Hejira starts when Muhammad and his companions left Mecca for Madina in what is known as Hijra. They were called Muhajirun. The Arabic root word for immigration and emigration is Hijrat. Over centuries, the term has been applied to a number of other Muslim refugee and emigrant groups.
- Muhajir Khwarezm, the Muslim refugees that escaped Genghis Khan's Mongol invasion of Muslim lands in 13th century and they settled in other Muslim lands not touched by this calamity. Maulana Jalaluddin Rumi fled Afghanistan and settled in Anatolia to escape the Mongol army.
- Muhajir (Albania), Albanians that used to live in Serbia (near Nis and Prokuplje), and were violently displaced through the ethnic cleansing exercised by Serbian army in 1878. As a consequence, thousands of them settled in Kosovo where they live today.
- Muhajir Crimean, the Muslim refugees of Crimean ancestry that settled in Ottoman Empire after the Russian Empire conquered Muslim Crimean Khanate.
- Muhajir (Caucasus), the Muslim population of Caucasus resettled to Ottoman Empire and Middle East after the Caucasian War.
- Palestinian refugees are Palestinians that were displaced by Israel's war of Independence in 1948-1949.
- Muhajir (Turkey), the Muslims of Balkan ancestry that settled in Turkey after the collapse of Ottoman Empire.
- Muhajir (Pakistan), the Urdu speaking Muslims refugees from India who settled in Pakistan after independence in 1947.
- Afghan refugees, Muslim muhajirs from Afghanistan who escaped the Soviet invasion in 1979 until the 2001 U.S. invasion in which the Taliban was removed.
After the Indian independence, the Muslims who had remained in India, or were born in India, were also sometimes referred to as Muhajir by the Pakistani people.
