mystery gift 

What you find when you stick long objects in holes that are too small.

David found a mystery gift in his friends hole.

mystery gift by NAGS October 31, 2013

mystery time 

Any short period of time forgotten during a long day of drinking.

John said he partied all day at the tailgate and that he had a little mystery time before dinner..

mystery time by Why is this not a word yet? January 11, 2016

mystery meat 

some kind of food you just can't tell what kind of meat is in it if any at all. prison food

shit we're having mystery meat for dinner tonight

mystery meat by lita ford September 24, 2017

Mystery Boner 

When your penis becomes erect for no apparent reason.

Guy 1: I just got a mystery boner man!
Guy 2: Cool!

Mystery Boner by HookTheGamer December 22, 2017

Mystery Marination 

The process when you're practicing a skill relentlessly but continuously fail to master it, but when trying again after a certain number of days, the skill comes naturally>

Zoe simply could not understand how she was able to play the piece correctly. The night before, her pathetic attempts to master bars 57 -79 held no results no matter how she practiced it, Today, however, she was able to perfectly play the piece on her first attempt. It seems that her playing skills had undergone a mystery marination overnight.

Mystery Marination by Chamber August 1, 2018

Mystery Roll 

Great looking guy, whose origin is unknown, but what is known is that he is one hell of a guy.

Damn, did you see that Mystery Roll at the Holiday Party.

Mystery Roll by Holiday Guy December 19, 2019

Mystery Blood 

Blood that suddenly appears for no immediately obvious reason, such as accidentally scratching an itch and you hand comes back with blood on it.

"I just scratched the back of my head and now I've got mystery blood on my hand, can you check back there?"

Mystery Blood by taerg_eht_oznobroc November 25, 2020