Servant who could be Eritrean (8)
I believe the answer is:
retainer
'servant' is the definition.
('retainer' can be a synonym of 'servant')
'could be eritrean' is the wordplay.
'could be' is an anagram indicator.
'eritrean' anagrammed gives 'RETAINER'.
'who' acts as a link.
(Other definitions for retainer that I've seen before include "Part payment down for an old servant" , "money to be paid in advance" , "Household servant (often faithful and old!)" , "Old servant - fee paid in advance" , "Fee; long-term servant" .)