Word on Irish euro coins (4)
I believe the answer is:
eire
'word on irish euro coins' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for eire that I've seen before include "Official name of the Irish Republic, 1937-49" , "Irish name for Ireland" , "Northwest European country" , "Gaelic name for Republic of Ireland" , "EU country" .)