extremist

noun

1. A person who holds extreme views, especially one who advocates such views; a radical or fanatic.

   “In Urif, extremists spray painted “Death to Arabs” on shipping containers belonging to a local resident and the local quarry was tagged with the words “Fight the enemy.””

   “Oy, mate! I'm an Australian extremist, and I've come to detonate this bomb that'll release all the world's deadliest spiders into... Did I pick a bad time?”

adj

1. Holding extreme views, especially on a political or religious subject.

   “There are some minor extremist movements that are antiforeigner.”

   “The hate crimes, once commonly referred to as “price tag attacks,” are committed by extremist Jewish youth from nearby settlements.”

2. Of or relating to extremism.