Taking your shirt off the second you get within twenty feet of water, regardless of how sloppy looking you are. Dignity and self-respect are meaningless when practicing 'sun's out, tum's out'.
Dude 1: Jody can't go near a body of water while keeping his shirt on. Check him out over there in the kiddy pool splashing water on his gut.
Dude 2: Sun's out, tum's out bro. Stop shaming.
Dude 2: Sun's out, tum's out bro. Stop shaming.
by joemammy August 2, 2019
Get the Sun's Out, Tum's Outmug. A phrase originating on South park. It was used to insult Rob Schneider and his various roles. Used to express that there's just no point in explaining how ridiculous his roles are.
by Kaira Pepper April 29, 2011
Get the Herp De Derp De Tittly Tummug. the act of or participating in or being a tum tum. The origins of this name are uncertain however it is known that this is the progression of a name started in 2005: "Tum Tum". AG started Tum Tweezy.
by Ryan Lefkoff December 16, 2007
Get the Tum Tweezymug. In 2015, The Coca-Cola Company purchased Tum-E Yummies and the brand continues to be produced and distributed exclusively through the Coca-Cola System
by SPrice1980 May 8, 2023
Get the Tum-E Yummiesmug. A "bum tum" is referring to a stomach ache.
"Bum" as in "bummed out" or " bummy"
"Tum" as in "tummy" or otherwise known as "stomach"
"Bum" as in "bummed out" or " bummy"
"Tum" as in "tummy" or otherwise known as "stomach"
"Hey Josh, I can’t make it to your bar mitzvah 2nite"
"Aw common Elliot why not?"
"I’ve got a bum Tum"
"Aw common Elliot why not?"
"I’ve got a bum Tum"
by Funky smells August 13, 2023
Get the Bum tummug. 
A hashtag meaning "Total Undergrad Move." An action or behavior typical of an undergraduate student.
by D Aurelio February 23, 2013
Get the #tummug.