In Islam and sharia (Islamic law), bidʿah (Arabic: بدعة [ˈbɪdʕæ], lit. 'innovation') refers to innovation in religious matters. The category is further divided into bid'ah al-ibadat and bi'da al-mu'amalat. The first category refers to innovations in sacred matters, such as worship, and are generally forbidden as it violates the textual source of the Quran and the Sunnah. The second refers to innovations in the mundane realm and is often permissible, as long as it does not violate the Sharia.
Linguistically, as an Arabic word, the term can be defined more broadly, as "innovation, novelty, heretical doctrine, heresy". In classical Arabic literature outside of religion, bidʻah has been used as a form of praise for outstanding compositions of prose and poetry. The alternative positive concept for bidah is maslaha.
