They're paid directly to the South (4)
I believe the answer is:
dues
'they're paid' is the definition.
'directly to the south' is the wordplay.
'directly' becomes 'due' (synonyms).
'to the south' becomes 's' (abbreviation).
'due'+'s'='DUES'
(Other definitions for dues that I've seen before include "Payments made for upkeep of church" , "Membership fees" , "Subscription to a club or society" , "subs" .)