Base 2.5 

It refers to a point in the base system between 2nd base and 3rd base. It is dry-humping. It has always seemed more than simple groping but it is less than the handjobs/blowjobs of 3rd base. Dry-humping now has a definite place on the base system.

guy1: hey, y'know the base system?
guy2: yeah?
guy1: wher does dry-humping go?
guy2: base 2.5
guy1: ok cool thats good to know
guy3: you guys are fucking retarded

Base 2.5 by uberjai July 27, 2012

Number 2.5 

When your standing there doing a piss and you feel a fart coming on but instead you shart yourself and now you have to sit down on the toilet to finish your shit whilst cleaning up the mess in your undies.

mate, why were you in the toilet so long?

I went in to do a piss and ended up cleaning myself up, bloody done a number 2.5 (two and a half)..

Number 2.5 by Wayne-Car May 12, 2017

Base 2.5 

Base 2.5 uses powers of 2.5 for the numbers, it is considered binary and Base 5 at the same time.

Oh look! Base 2.5 isn't used! What a bad day!

Base 2.5 by MandullorTheBEEKER October 31, 2021

Despacito 2.5

The most holy piece of literature and art to ever be created. Thousands seek out this masterpiece, but alas none have yet found it.

Phil: have you heard of Despacito 2.5?
Normie: why the fuck are you in my house! What the hell are you talking about! I told you if you set foot on my yard again I was calling the police!

Despacito 2.5 by Carl Urban July 14, 2018

Harrier 2.5 

Harrier 2.5 is fookin trash 🗑️🗑️🗑️. Literally the worst car ever made, the most ugliest one to exist rides on some cheap chinese reps and a fake modellista bodykit with bangla bumper on it eww. Even has a restitched red steering from AutoZone cuz why not the owner is fucking gaay

Man she a harrier 2.5
If I had to choose between death and a harrier 2.5, I'll be having dinner with Satan in a few days

Harrier 2.5 by damnshawtythatfine January 15, 2022

Clickteam Fusion 2.5 

Clickteam Fusion 2.5 is the upgraded version of Multimedia Fusion and uses a better rendering engine then previous versions, the current revision is 293.1

I used Clickteam Fusion 2.5 to make a Five Nights At Freddy's game.

Clickteam Fusion 2.5 by Knowledge Potato March 18, 2021

Blessthefall 2.5 

Blessthefall 2.5 are an awesome post-harcore band, who are famous on the website tumblr. They are well known for their single 'God Wears Gucci Skirts', and have toured with the likes of The Devil Wears Prada Shoes and All Time Low 2.5

Person A:"Blessthefall 2.5 are coming to town!!"
Person B: "ARE THEY THE BAND OFF TUMBLR?!"
Person A: "YES!!!"
Person B: "WOOOO LETS GO!"

Blessthefall 2.5 by btf 2.5 fan!! October 25, 2009