When a male or female starts masturbating in the ocean.
Example 1: You guys go and enjoy your surfing. I'm just going to stay here and sea mine.

Example 2: I apologise, but this beach is closed to the public as there are too many sea mines.
by xSonic Hedgehog April 7, 2015
Get the Sea mine mug.
The process of a man inserting a bike/ball pump into his urethra and pumping it up causing his bladder to expand and then inevitably explode inside of him. Usually done with a hand pump, but an electrical equivalent can be used for the daring.
Guy 1: Dude, why do you have that pump? You don't even own a bike.
Guy 2: Oh, I'm planning to enjoy a Yugoslavian Sea Mine this evening...
by Joshua Durry September 1, 2018
Get the Yugoslavian Sea Mine mug.