Noun: Alcohol. A drink which, if consumed in sufficient quantities makes you forget large episodes of your life. A popular phrase due to its assonance with the patent medicine 'Milk of Magnesia'.
"...and while dancing you unzipped her dress and pulled it to the floor. Then you pissed in the bride's champagne glass and honked up all over the cake."
"Yes, I remember every bit of that. Just tell me how come I woke up this morning in the driver's seat of my car outside my house?"
"Put it down to the milk of amnesia."
"Yes, I remember every bit of that. Just tell me how come I woke up this morning in the driver's seat of my car outside my house?"
"Put it down to the milk of amnesia."
by McCririck's unlucky Laundress October 2, 2005

When immediately after sex you cannot remember why it was you decided to have sex with this person in the first place. Experienced more by men, but not exclusively. This is not a medical emergency as the symptoms typically fade within 24 hours at which time you want to have sex with that person again.
Seconds after sex...
Girl to Boy: Hey, that was amazing. You're so hot!
Boy to Girl: Who are you and how did I get here?
Girl to Boy: Oh no, bad case of Sexual Amnesia. Here's my number, call me tomorrow.
Girl to Boy: Hey, that was amazing. You're so hot!
Boy to Girl: Who are you and how did I get here?
Girl to Boy: Oh no, bad case of Sexual Amnesia. Here's my number, call me tomorrow.
by Duece79 June 4, 2018

by Kingsman November 16, 2017

A mental phenomena in which the pooper pushes violently to the point of completely losing his/her train of thought. Can have long term effects.
I opened safari on my phone while on the toilet and before I could type my search in, all hell broke loose for a total of 3 seconds. When it was over, I couldn’t remember what I was going to look up. I had experienced poop amnesia.
by FattyOmega January 21, 2021

“Hey I’m having the serious case of dick amnesia because that summer with John was so much fun. But now that we broke up I have nothing.”
by Ineeddick March 12, 2019

by wreckingdrew December 15, 2011

When start or are about to do or say something then you either forget about it or space out while doing said action. The phenomenon in which you do or are about to do something and forget why you wanted to or did it in the first place.
I was opening a cabinet then I forgot why I opened a cabinet, therefore why I named it Cabinet Amnesia.
by Zekurom May 13, 2020
