5-O

five-oh

The police. The term comes from the TV show Hawaii Five-0, about police officers in Hawaii, the fiftieth (50th) state. The five-oh are closing in on us—how are we going to avoid being arrested?
Farlex Dictionary of Idioms.

5-O

verb
See five-oh
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • five-oh
  • take five
  • give me five!
  • give me/gimme (a) five
  • give somebody five
  • give someone five
  • go nap
  • five will get you ten
  • hang five
  • slap (one) five
References in periodicals archive
There's a lot of fans of "Hawaii 5-O" out there and it is of interest to these visitors to come to places where the shows that they love are made.
Best in show
Rowley and Appleyard, back to back on the big ledge: Rowley-Frontside 180 nosegrind, and Appleyard with the switch 180 to 5-O.
WORLD WAR III
However, as we all have come to understand, the big 5-O doesn't have to stand for middle age.
Hawaii (Business) 5-O