Old African country in South Africa or one elsewhere (7)
I believe the answer is:
somalia
'one elsewhere' is the definition.
I can't tell whether this defines the answer.
'old african country in south africa' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'african country' becomes 'mali' (country in Africa).
'in' means one lot of letters goes inside another.
'south africa' becomes 'SA' (abbreviation).
'o'+'mali'='omali'
'omali' inserted inside 'sa' is 'SOMALIA'.
'or' is the link.
(Other definitions for somalia that I've seen before include "Country of East Africa" , "Mogadishu its capital" , "E. African state" , "East African country" , "Horn of Africa country" .)