'really' or 'very'
'thats sum cool!' or 'hes sum hot!'
by i have no life May 13, 2005
Get the sum mug.
When one Sings and Humms at the same time! It is quite a pleasant sound a bit like a young walrus' mating call!
I was walking down the street Summing to myself
by Chemshotlord August 31, 2015
Get the Summing mug.
The ratio of seats to bums on public transport, particularly relevant to rail travel.
Southeastern never seem to get their sums right!
by EmptyPots March 24, 2015
Get the Sums mug.
Acronym for "Super Ultra Mega Slap"

Used when insulting or scolding someone for what one thinks is tasteless, immoral, or just fucking retarded.

May also be followed by an actual slap.

Coined in 2004, by a kid with an itchy fro and another kid who was just trying to fit in.
Me - Hey Colton, I just went out and bought the new Nightmare Creatures game!

Colton - *SUMS*
by superskiier July 11, 2008
Get the *SUMS* mug.
an instagram account made by a boy where he posts pictures of himself pretending to be a woman
look at him, he's posting for sum sum ig again!
by averyone's mr tang April 13, 2021
Get the sum sum ig mug.
A guy with a huge mule who likes to talk dirty to women.
Look at Sum, he's a stud.
by Sum's Lover November 12, 2003
Get the sum mug.
A game where when someone says something stupid and you get to hit them on the head for it. After someone says the stupid statement, you immediately say "That's sum." while rubbing your fingers in the air like the sign for paying money.
Mick, "I drank 7 out of the last 5 days"
Al & Calvin, "That's sum, asshole (rubbing fingers in the air)."
then Al & Calvin each get to slap mick on the top of the head.
by a. ryan May 22, 2006
Get the sum mug.