Irishman may be apt (3)
I believe the answer is:
pat
'irishman' is the definition.
(Patrick is a common Irish name)
'may be apt' is the wordplay.
'may be' indicates anagramming the letters.
'apt' anagrammed gives 'PAT'.
(Other definitions for pat that I've seen before include "Tap lightly" , "Touch gently; glib" , "Touch lightly - bit of butter?" , "Hit lightly" , "Portion of butter" .)