Spanish accent (5)
I believe the answer is:
tilde
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">spanish accent</span>' is the definition.<br/ ><span class="explanation-format__explanation">(accent mark written over n in Spanish)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for tilde that I've seen before include "Sign on Spanish character" , "Significant mark" , "Spanish accent, as in se-or, ma-ana etc." , "senorita lacking one?" , "Spanish accent sign" .)