Sensation of dizziness (7)
I believe the answer is:
vertigo
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">sensation of dizziness</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 vertigo that I've seen before include "the Eiffel Tower effect" , "Dizzy feeling when at great height" , "attack at altitude?" , "source of imbalance" , "Sensation of dizziness caused by heights" .)