Single fact (5)
I believe the answer is:
datum
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">single fact</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 datum that I've seen before include "Minimal information" , "Given piece of information" , "Little bit of information" , "Given item" , "bit of info" .)