Municipal head from Irish county? Right (5)
I believe the answer is:
mayor
'municipal head' is the definition.
(I've seen this before)
'irish county? right' is the wordplay.
'irish county?' becomes 'mayo' (I've seen this before).
'right' becomes 'r' (common abbreviation).
'mayo'+'r'='MAYOR'
'from' acts as a link.
(Other definitions for mayor that I've seen before include "City manager" , "Local bigwig" , "Municipal head" , "Civic head of town or borough" , "Elected city head" .)