1. To escape; to vanish or disappear. (Not necessarily in a southerly direction.) Everyone in the gang headed south when they learned that the police had discovered their hideout.
2. To fall or drop; to depreciate; to lose quality or value. (Especially related to finances or stock exchanges.) The company's stock profile continued heading south for the third day in a row today. I used to be a big player in the stock market, but all my investments have headed south lately.
3. To cease working or functioning; to quit, fail, or fall apart. Talks between the labor union and the construction firm headed south yesterday, so it looks like workers will be on strike again soon. My computer is only a month old, and it's already heading south.
If something heads south or goes south, it becomes less successful or falls to a lower level. At that point, the stock market headed south. Managers were selling shares in the certain knowledge that the company was going south.
2008 Newsweek Many months ago, McCain remarked, honestly, that he didn't know much about economics. As the economy heads south, he is routinely reminded of his candor.
head ˈnorth/ˈsouth(business) (about share prices, currencies, etc.) rise/fall in value: The country’s currency headed south for the second day, weakening 1.4%.
See go South