Slang term: A person's 30th year of life. Typically a 30th Birthday term representing one surpassing their 20s to enter the "dirty" part of life. Adulthood. Dirty 30 celebrations tend to be a night full of drunken debauchery. Full of bad decisions, vomit, and unnecessary semen in random places.
"Marrisa is turning 30 this year."
"Ooooh shit. Goodbye 20s. Time for a Dirty Thirty party!!! No black lights. I still have cum stains on my jeans from Stephanie's dirty 30 party last year. "
Male testicles that range from the age of 30-39. These testicle tend to have problems, this is when men should get their sperm count checked and make sure they have a lively swimmers. If a male has a lack of ability to hold a woman, it must be because his balls don’t work. This is a common theme for people named Daniel. More than likely it has to to do with looks, but their testicles get saggy and sweaty throughout this 9 year period. Most women do not like a man with “Dirty 30’s”, especially those who do not get them checked out. Damage to the testicles may also expedite this process.
Person 1: Dan, you suck at dating!
Person 2: No I don’t! It’s women being women!
Person 1: Dan, it’s your dirty thirty’s! Most women and little girls don’t want that, they want Man Balls!
Greg, Erik, Matt, and Daemon were dissapointed that The Dirty Thirty in their hotel room didn't involve any action. They later realized it was because the couple wasn't knocking boots they were making love.