to move away from the enemy after being defeated in battle [≠ advance]:
The rebels retreated to the mountains.
They were attacked and forced to retreat.
to move away from someone or something:
He saw her and retreated, too shy to speak to her.
retreat to/from/into etc
Perry lit the fuse and retreated to a safe distance.
It was not a conscious choice to retreat from public life.
if an area of water, snow, or land retreats, it gradually gets smaller:
The flood waters are slowly retreating.
to decide not to do something you were planning to do, because it was unpopular or too difficult
change your mindwritten
The Canadian government has retreated from a plan to kill 300 wolves.
to go away to a place that is quiet or safe
After the noise of the city he was glad to retreat to his hotel room.
to ignore what is happening around you and give all your attention to your private thoughts
if shares etc retreat, their value falls to a lower level