(informal) The Beatles.

(slang, Canada, US) A lowly, disreputable cheat or fraudster, especially at cards, especially a dull or unimaginative one.

(motor vehicles) A four-speed manual transmission whose gearshift lever is mounted beside the driver on the floor of the vehicle.

Alternative form of fourball (“golf format”)

(informal, humorous, figuratively) A notional weapon used to knock sense into the clueless.

Alternative form of clue-by-four

(US, slang) To win something four times consecutively.

(US, slang) A fourth successive win.

Alternative form of four o'clock

Having four wheels / Having a transmission that drives all four wheels.