1. Someone who believes only their way, and everyone else is wrong.
2. Someone who is obsessed or stuck on one false belief and ignorantly denies logic and reasoning.
3. A derogatory term that Atheists use to describe Christians and other religious people.
2. Paul listens to the Bee Gees and drives a Trans Am. He's delusional on the 70s, man.
Person 2: OMG UR DELUSIONAL
Person 1: No I am not, I've thought about the issue thoroughly
Person 2: DELUSIONAL DELUSIONAL DELUSIONAL IM GONNA HAV U LOKD UP
2. H/Hr shippers
Me: You're incredibly delusional... If you could read you would realise Ron and Hermione have amazing amounts of sexual tension...
2. Used to describe someone attached, possibly obbsessed, with an idea which is either false, or has changed. Synonymous to "living in the past."
HeronShipper: A delusional has entered the room, folks.