armnesia 

When you raise your arm you forget what you were going to say to the teacher of the classroom.

When I raised my hand, my teacher called on me and I had a sudden struck of armnesia.

armnesia by Jonathan Lamones March 15, 2008

Repetitive Familiarity Amnesia 

The inability to remember if you did something you do every day.

Every morning when you leave the house, you push the button on the garage door remote closing the garage door. Then 10 minutes later, you can’t recall if you closed the garage door because you do the exact same action at the exact same time every morning, so they all blend together and you couldn’t tell if your memory was from that morning or any of the previous mornings where you went through the same motions like you have countless times before. You just experienced Repetitive Familiarity Amnesia.

Repetitive Familiarity Amnesia by TheChrisenator July 20, 2021

selective amnesia 

to benefit oneself by pretending to forget.

"Dude, if I loan you this twenty dollars please pay me back. Don't come down with a case of selective amnesia on me."

selective amnesia by Mack C January 21, 2007

Post-Amnesia

(noun) - When someone makes a comment regarding a post on Facebook or tweet that you completely forget about.

Jody: So did you end up all wet this weekend?
Chuck: Excuse me?
Jody: Yeah you facebooked it was raining at your cabin.
Chuck: Ohh riggghhhhttt... Sorry, Post-Amnesia

Post-Amnesia by ITALUS September 12, 2011

Nostalgic Amnesia 

noun; a state of mind where one experiences a pleasant glow due to a combination of reminiscences of a past time, and completely forgetting how rubbish that time was whilst you were originally experiencing it.

Nostalgic Amnesia had set in, and Frodo found himself pining for the glory days in Mordor.

Nostalgic Amnesia by Dr Winterbourne February 21, 2009

Convenient Amnesia 

*noun* (until someone starts doing it too much, then it changes to a verb) pronounced kun-veen-nunt am-nee-shia

1. Pretty much whenever a certain someone/something is wrong (which is plentiful), he/she/it retracts by saying something totally asinine to cover himself/herself/itself up and try to still prove that he/she/it is right. Basically used to being remembered facts to twist reality.
2. Forgetting certain facts of an area to twist things so you cannot be proven wrong.

*Circa 1999, Location; Phoenix area Best Buy*
Milo: Bro, I've been waiting 18 years for this new Star Wars film to come out! You as excited as I am?
Conner: Yeah! I've been a huge fan my whole life!
Milo: I hear they're introducing a whole bunch of new characters, new Jedi's, a young Anakin Skywalker, and they introduced his mother Shmi (pronounced shmee)
Conner: Naw bro, her name is shimmy
Milo: I just looked at the book that we sell here and its spelled S H M I and phonetically it sounds out shmee
Conner: Yeah, but is pronounced shimmy
*argument ensues for several months*
*premiere night for Phantom Menace arrives*
Qui Gon Jinn: Hello, my name is Qui Gon Jinn
Shmi: My name is Shmi (pronounced shmee) Skywalker
*Milo looks at Conner and smiles. Also see getting palled*
*several years later*
Conner: Incorrect! No bro, it was episode II, 2002, AND it was you who thought it was shimmy!
Milo: Wow, convenient amnesia!! But here is where your argument is flawed broseph. Don't you think by episode 2 I would have known her name was pronounced shmee?

Tony: Dude, me n my boy were talking about the transformers sound and when it happens in the movie vs. when it happens in the cartoon.
Conner: Its when Barricade transforms in the beginning.
Tony: No way, that was Blackout. Blackout is the helicopter.
Conner: No, Barricade is the helicopter.
Tony: Let's look it up.
*after a quick few keystrokes on the interweb*
Tony: There it is. Blackout is the helicopter. You just got palled son.
Conner: Whatever, I never said he wasn't
Tony: Wow. What Convenient Amnesia!

Convenient Amnesia by The Tang Bang Crew May 23, 2008