Tribal leader (5)
'tribal leader' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for elder that I've seen before include "Tree - wise counsellor" , "Patriarch" , "Senior leader" , "More senior in years" , "Shrub, tree" .)
(Other definitions for sheikh that I've seen before include "leader of Arabs" , "Leader of an Arab family" , "Broadcast upset" , "Disturbance of the peace; brawl" , "Arab tribal leader" .)