Mnemonic Device
From Gomerpedia
A mnemonic device is a common learning technique used by medical students to help remember knowledge in the immediate future only to find that a few weeks to months later all they remember is the mnemonic itself but not the thing that it stands for.
Example
Student 1: Hey, do you remember the carpal bones in the hand?
Student 2: Of course I do! It's "Some Lovers Try Positions That They Can’t Handle."[1]
Student 1: Yeah, but what does the mnemonic stand for?
Student 2: No clue.
References