dolusional 

characterised by holding idiosyncratic beliefs or impressions similar to those held by Roger Hill "Dollar Bill", that are contradicted by reality or rational argument, typically a symptom of mental disorder.

You seriously think you can out drive Rory McIlroy, you are dolusional!

dolusional by urbanauthor2020 February 21, 2020

delusional 

Believing something to be true that is clearly not. Someone who is not thinking clearly. Used to describe someone attached to an idea which is obviously false.

Jon believes he is always right. He's delusional.

delusional by youreajackass April 16, 2014

Delusionary Fanboy Syndrome 

1. Someone suffering from a belief that there favorite character is a super cool badass based of them just liking the character. The character in question can have no feats near what a person suffering from DFS says he can do.
Ex: A person suffering from DFS would think Krillin is the strongest fighter in DBZ and would be strong enough to fight Perfect Cell and win with no help.

2. Someone suffering from a belief of their favorite characters needing extra care/exposure when they serve no real purpose to the overall story arc of the series they are in. They make up random scenarios to put their characters in, but unlike fan fiction writers it is their own headcanon that they try to spread to everyone.

"Stephanie Brown would mop the floor with Batman in his prime"
"Robert, you are suffering from Delusionary Fanboy Syndrome"

Delusionary Fanboy Syndrome by Mr_JayJay24 April 28, 2020

Delusional 

When someone clings to the opinions in their head despite the facts. Often times these people do not want to measure the accuracy of their opinions and believe their situation is overly unique.

Tom is delusional, he thinks he is the best parent in the world but his kid is 4 years old and cant spell his own name.

Delusional by Dilemmas.co November 16, 2020

delusionalship 

A one-sided love where you constantly think someone is dropping you hints or has a crush on you whilst it's all in your head (a delusion) and they don't actually care.

"I can't believe I was in a delusionalship with her for so long"

delusionalship by rektx March 6, 2023

delusionable

from the latin delusio, the act of being delusional, as coined by a MSFT technologist

That person is delusionable

delusionable by GiveUntoCaesar August 13, 2007

delusional cockbag

A seemingly intelligent individual whose perception of reality (i.e. value as a human being, ability as a parent or child, importance as a social and moral leader, skills as a lover) is so distorted that no amount of logic, reason, or compassionate pleading can sway them from supporting the Bush administration

My dad has become the king of the delusional cockbags without even trying.

delusional cockbag by NumbaOneSon December 15, 2008