Irish national symbol (4)
I believe the answer is:
harp
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">irish national symbol</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for harp that I've seen before include "Stick to one theme" , "Stringed instrument" , "Heavenly instrument?" , "Talk tiresomely using upright musical instrument" , "Lyre" .)