Five-O

Five-O (noun / slang)

(Also written as: 5-0, Five-Oh)

Definition: The police. Uniformed plod, unmarked patrol cars, or law enforcement generally. Mostly hollered as a heads-up that sirens or blue lights are incoming.

Pronunciation: /faɪvˈoʊ/

Where It Comes From: Blame 1970s American telly.

The original crime drama Hawaii Five-O got its title from Hawaii being the 50th US state. Decades later, 90s hip-hop artists (think Cypress Hill and Ice Cube) turned “5-0” into universal slang for sirens and badges. Between pirated US tapes, Grand Theft Auto: San Andreas, and early UK road rap tracks, London schoolyards and estates just nicked it outright to sit alongside traditional terms like the Old Bill.

How People Actually Use It: Usually spat out in a hurry when someone spots blue lights.

If a squad car pulls up outside the off-licence or an unmarked Astra crawls down a side street, someone whispers “Five-O” so everyone puts away whatever they shouldn’t be holding. It gets dragged out on everyday drives as well—usually when a mate clocks a speed camera van hiding behind a hedge on the dual carriageway.

Examples in the Wild:

• “Tap the brakes mate, Five-O are parked up in the layby ahead.”

  Translation: “Slow down, there’s a police speed trap around the corner.”

• “Someone rang Five-O on the garden party before it even properly kicked off.”

  Translation: “A neighbour complained to the police about our noise.”

• “He clocked the Five-O round the corner and immediately crossed the road.”

  Translation: “He spotted officers approaching and walked in the opposite direction.”

Similar Slang: Old Bill, Feds, Coppers, Rozzers, Plod, Fuzz, Pigs