noun

• (countable, Islam) A Muslim scholar and interpreter of sharia law, who can deliver a fatwa.
  "Mujtahidd's online claims have prompted an aggressive backlash against social media from the Saudi religious establishment. The grand mufti of Saudi Arabia, Sheikh Abdul-Aziz al-Sheikh, said in January that Twitter was a platform for "promoting lies" and a "dangerous practice" that should be avoided by Muslims. Commentators have described the phenomenon as symbolic of the growing political debate about use of Twitter in Saudi Arabia."
• (uncountable, Australia, British, New Zealand) A civilian dress when worn by a member of the military, or casual dress when worn by a pupil of a school who normally would wear uniform.
  "He had a suit of summer mufti, and a broad-brimmed blue beaver hat looped with leaves broken from the hedgerows in the lanes, and a Leander scarf tucked full of flowers: loosestrife, meadowrue, orchis, ragged-robin."