Civic dignitary from Irish county on ship (8)
I believe the answer is:
mayoress
'civic dignitary' is the definition.
(I've seen this before)
'irish county on ship' is the wordplay.
'irish county' becomes 'mayo' (county in Ireland).
'on' becomes 're' ('on' can be mean 'with reference to').
'ship' becomes 'SS' (prefix in ship names eg SS Great Britain).
'mayo'+'re'+'ss'='MAYORESS'
'from' acts as a link.
(Other definitions for mayoress that I've seen before include "Town/city dignitary" , "Female dignitary" , "Public official" , "Civic dignitary" , "Local dignitary" .)