Profoundly (6)
I believe the answer is:
deeply
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">profoundly</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for deeply that I've seen before include "Profoundly" , "With intense feeling" , "In a profound way" , "fathoms down?" , "Thoroughly" .)