Curbs In - Curbs Out

Hang ten.

Totally tubular.

Curbs in, curbs out.

They might all sound like surfer lingo, but the third phrase is market slang for when financial exchanges break the glass to stop a short-term trading crisis. "Curbs" are circuit breakers, defined as restrictions on trading stocks, commodities, or even on the entire market when prices fall by a certain amount.

When investors say, "curbs in," it means that the circuit breakers are in effect. Trading is suspended or halted for a period.

Circuit breakers exist on exchanges all around the world. The New York Stocks Exchange introduced its own set of curbs shortly after Black Monday in 1987. The SEC has set Curb rules under Rule 80B of its code.