Mujaddid ( Larabci: مجدد‎) a musulinci shine mai kawo canji wanda aka bashi aikin cire kurakurai da suka faru tsakanin musulmai.Aikinsu shi ne nuna wa mutane gaskiyar addini wacce za a nemi al’ummar Musulmi su fuskanta. Dangane da shahararrun al'adun musulmai, ana nufin mutumin da ya bayyana a kowane ƙarni na kalandarmusulinci,ya tsarkake shi daga wasu abubuwa na daban kuma ya mayar dashi zuwa tsarkakakken tsarkin sa.A zamanin yau, ana kallon mujaddadi a matsayin mafi girman musulmin karni. Ikhtilaf (rashin jituwa) ya kasance tsakanin masanan hadisai masu ban tsoro. Malamai da masana tarihi kamar Al-Dhahabi da Ibn Hajar al-Asqalani sun fassara cewa kalmar mujaddid ita ma ana iya fahimta a matsayin jam’i, don haka suna nufin ƙungiyar mutane. "Haƙiƙa, Allah (Allah) yana aikawa (ko kuma zai tashe ta) wannan al'ummar (al'ummar musulmin) a kan (farkon ko ƙarshen) kowane shekara ɗari wanda zai sake (ko kuma rayar) ta  addini" Kalmar larabci ta mujaddid na nufin "mai kawo canji", "mai gyara", "mai rayarwa", "mai sabuntawa" ko "mai sabuntawa".