Wireless pioneer
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">wireless pioneer</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for marconi that I've seen before include "Pioneer of radio communication from Minorca" , "Guglielmo --, inventor" , "Developer of radio telegraphy" , "Wireless inventor from Minorca" , "Italian electrical engineer, d. 1937" .)