(fawls-hahy-merz) A condition that causes memories to be twisted, exaggerated, or to materialize out of nowhere. Falseheimer's victims follow a pattern of exaggerating the length, the intensity, or number of occurrences of events by a particular multiplier. Victims of this condition may also claim to have thought of something first even when they have no clear evidence or memory of how it happened.
Your family watches Donnie Darko. The part is seen when Donnie calls his mom a bitch. You yell at your mom to not get in front of the TV to change the volume, but she proceeds to do so several times. Thirty minutes later she mentions not only of you yelling at her, but she also claims you have called her a bitch, which you have not. Mommy has Falseheimer's.
Falseheimer's: (noun) A feigned non-medical condition which symptoms include selectively forgetting things previously learned for the sake of expediency/convenience and forgetting to do chores in which one has no interest. Spouses and retail associates are particularly prone.
You forgot today was my birthday even after I told you three times a day all last week????? That's not a senior moment, dear: You have Falseheimer's."