Changes direction, ever moving south (5)
I believe the answer is:
veers
'changes direction' is the definition.
(I've seen this before)
'ever moving south' is the wordplay.
'moving' indicates anagramming the letters.
'south' becomes 's' (synonyms).
'ever' with letters rearranged gives 'veer'.
'veer'+'s'='VEERS'
(Other definitions for veers that I've seen before include "Changes direction abruptly" , "Turns sharply" , "Swerves" .)