Top definition
1.) (Internet slang) Shut da fuck up.

2.) South Dakota Farmers Union.
by Nigga, please. December 08, 2004
Get a sdfu mug for your mate Riley.
Jul 26 Word of the Day
Noun: a friend who is usually only called upon by a friend when a more primary/prominent friend is unavailable.

Taken from the term “second string” in an athletic competition situation. In football, if the star quarterback gets injured during a play, the second string is called off the bench to replace him/her. A “Second String Friend” is essentially benched until needed, if ever.

Synonyms: Plan B, Second Choice, Secondary Friend, Benched Until Needed
I got a call from X the other night. She had an extra ticket to a concert she bought for a friend, but they couldn’t make it so she called me to ask if I wanted to go because I am her Second String Friend.
by Deus-ex-machina August 26, 2020
Get the Second String Friend neck gaiter and mug.
2
Shut da fuck up. Used when chattin in a chat room.
When u in the chat room and sumone talkin to and u dont wanna talk to them.

Man sdfu talkin to me.
by Donna September 27, 2004
Get the sdfu neck gaiter and mug.
3
Shut Da Fuck Up.

Used by gangstas on Habbo.
Habbo Gangsta: SDFU bitch! *stabs*
by cjisn199a May 12, 2009
Get a sdfu mug for your cat Nathalie.
4
sdfu: shut da fuk up

(slang term: shut the fuk up)

when somebody ask a stupid question yu be like “ay sdfu”
Person: the earth is flat

Me: “ho sdfu 🤦🏽 ♀️😭.”
by tht one kid across the street. February 06, 2020
Get a sdfu mug for your barber Trump.