Mystery liquid

something you should never. EVER. drink. If you drink it, you will probably die.

guy 1: don't drink that mystery liquid!
guy 2: I wasn't gonna, retard.

by SailorJazzy<3 September 20, 2023

mystery mutt

a mixed breed dog of unknown breed origin.

a dog that resembles many different breeds.

my dog looks like she could be a shepard/jack russell/sheltie or a whippet/collie/border collie or a corgi/shepard/whippet or a smooth collie/jack russell....she's a mystery mutt.

by Lisavi April 6, 2008

Mystery shopper

Another word for a secret shopper.

I’m so excited about my new mystery shopper side gig!

As a mystery shopper, even your friends shouldn’t know what you do. It could blow your cover on a job

by Jozéy January 1, 2021

head unit mystery

The phenomenon where the original head unit of a test car is unknown, as its head unit has already been swapped with an aftermarket one

I couldn't figure out why the sound quality was so amazing during the test drive—turns out it was just a head unit mystery with that aftermarket stereo!

by Emotional Cruiser October 12, 2025

Mysterious Oysters

(slang) Typically used when talking about Psychedelic Mushrooms hitting really hard, or either looking to take a strong trip on Mushrooms.

Friend 1: "Last night we were everything everywhere!"

Friend 2: "Dayum broski we were certainly on another quest for the Mysterious Oysters!"

by 13AquaOrbit January 25, 2023

mysteri

Some one else

She is Mysteri.

by Rhsbdjejjsnfnej November 30, 2016

Mystery meat

When you aren't sure how big/small a guy's dick is

My new boyfriend really has a mystery meat.

by Samiejo816 November 17, 2016