go south

Verb

go south (third-person singular simple present goes south, present participle going south, simple past went south, past participle gone south)

1. (idiomatic) To become unfavorable; to decrease; to take a turn for the worse.
   • I should have walked away from the casino when my luck went south, but I stayed and ended up in the hole.
   • I still had 5 miles (8 km) or so to go to cross the river when all of the controls went south. The bird pitched up, shuddered, rolled right like it was going to spin […]1967, Bill Sparks, Wild Weasel mission 5 November 1967

   Synonyms:

   go downhill, go left, head south, move south, turn south, atrophy, break down, crack, decline, deteriorate

2. (intransitive) To make an escape; to disappear.
   • He won! A disbeliever, from childhood, in the frequency of miracles, he gathered up seven hundred and forty dollars and "went south" with it.1929, Peter B. Kyne, The Parson of Panamint and Other Stories, page 197
   • […]she decided to tape the DVD off to VHS and give that to the kids -- that way she could make a fresh VHS copy when the first one went south.2004, Cory Doctorow, Microsoft Research DRM talk
3. (slang) To give somebody oral sex.
4. (slang) To rathole: to take chips off the table in a cash game without exiting the game completely, especially with the intention of limiting losses.