1. Someone who is always itching to get on their soap box and preach to everyone about political correctness whenever somebody says something they think could offend someone else, when it honestly isn't necessary or needed except to annoy the crap out of everyone.
Friend 1 - "Amy yelled at me the other day for using the term 'Mexican'. I never knew I wasn't allowed to say where someone was from...."
Friend 2 - "Yeah, she's a total overreactivist."