Lives on borders (7)
I believe the answer is:
resides
'lives' is the definition.
(to reside somewhere is to live there)
'on borders' is the wordplay.
'on' becomes 're' (regarding).
'borders' becomes 'sides' (I've seen this in another clue).
're'+'sides'='RESIDES'
(Other definitions for resides that I've seen before include "stayed in Scotland" , "Sojourns" , "Lives, dwells" , "stays in Peebles" , "stays required" .)