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9.
5-O
a patrol car.

Orgin: late 80's Cali.

back then all police cars at one time where Mustangs, 5.0 engine model, on the front and side of the car it read in chrome letters the engine model. 5.0.

it refers to the car they patrol in.

now it also refers to the police officer himself.
"5-O keeps making rounds through my neighborhood like we are causing problems".
by Lec2 February 09, 2003
 
1.
5-O
5-O goes back even further than California late 80's. It's origins are a reference to an old 70's TV show called Hawaii 5-0 starring Jack Lord. The police were 5-O and eventually the show lingo caught on as hip among petty criminals in southern California.

"STOP, Hawaii 5-O!!!!"

....blah, blah, blah- small struggles, throw a few punches - handcuffs criminal and stuffs them in the back of a patrol car ....

"Book 'em Danno", said Steve Garrett.
by ex-wife of 5- Oh April 26, 2003
 
2.
5O
The 5O or more appropraitely, 5-O, refers to the police forces, usually by parties that do not like them.
Here comes the 5O, run!
by Gumba Gumba April 14, 2004
 
3.
5-O
5-0 became a slang term for law enforcement (aka police) after the hit show "Hawaii Five-O". The show was centered around a fictional division inside the State-Police of Hawaii and carried the same name as the television show ("Hawaii Five-0". The division's name gets its origin from honoring the fact that Hawaii was the 50th state to become apart of the United States of America.
On a side note, the division was actually called "Hawaii Five-0" (as in Zero, no the letter "o") but IMDB has the show listed with the letter "o" in the tittle.
The Five-0 (5-O)had set-up a speed trap and gave me a hefty ticket!
by RichieV April 12, 2007
 
4.
5-O
police, the cops, po po
yo, it's 5-O
chill man we aint da 5-O
by dbam December 03, 2005
 
5.
5'O
when you're doing something you're not supposed to be doing and someone yells 5'0 that means they're giving you a warning because you're going to get caught
say you're looking through the teachers drawer and your friend is on the look out and see's your teacher coming, he/she will yell 5'O so you can be warned and pretend like you're innocent
by SSSSS333 January 18, 2009
 
6.
5-O
The police. 5-O is the type of engine that police cars use.
"Hey lets get the fuck out of here the 5-O is coming!!"
by Vivianna April 03, 2008
 
7.
5-O
An extremely cheap, pretty harsh vodka. Usually the cheapest you can find, stands for 5 - o clock.
(guy): Man that vodka was dank.

(other guy): Fuck no, that was 5-O.
by Walshyy March 03, 2009