Certain something (2,2,4,4)
(Other definitions for je ne sais quoi that I've seen before include "Elusive but pleasing quality" , "(A certain) something" , "Quality that can't be easily described" , "Something indescribable (French)" , "Indefinable quality" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">certain something</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 aura that I've seen before include "Intangible atmosphere" , "Mystic air" , "Indiscernible quality" , "Atmosphere [ital]" , "Air, distinctive quality" .)