Doctor investing in a foreign currency (5)
I believe the answer is:
dinar
'foreign currency' is the definition.
(I've seen this before)
'doctor investing in a' is the wordplay.
'doctor' becomes 'dr' (abbreviation).
'investing' indicates putting letters inside (inserted letters are taken in or invested).
'in'+'a'='ina'
'dr' going around 'ina' is 'DINAR'.
(Other definitions for dinar that I've seen before include "Yugoslav currency" , "Middle Eastern currency" , "Currency unit of Algeria, Libya etc" , "Iraqi CURRENCY" , "money" .)