Very, informally (4)
I believe the answer is:
real
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">very informally</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 real that I've seen before include "foreign currency" , "Pukka" , "Genuine, not imitation" , "Spanish football team" , "Not imaginary, genuine" .)