go south
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.
ADJ.
arctic, central, east, magnetic, next, north, pacific, smaller
The magnetic south pole has shifted significantly over the past century.
VERB + SOUTH
arrived, come, comes, flows, flying, going, look, tends
The river flows south through the valley before reaching the sea.
SOUTH + NOUN
africa, america, denmark, england, highway, islands, japan, pole
We drove down the south highway for hours before stopping for lunch.
PREP.
from, in, into, out, since, than, toward
We drove south from the city and reached the coast by evening.
ADV.
away, ever, then
The birds flew away south for the winter every single year.