Correctness, precision (8)
I believe the answer is:
accuracy
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">correctness</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(accuracy is a kind of correctness)</span><br/ ><br/ >'<span class="explanation-format__original">precision</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ ></span>
(Other definitions for accuracy that I've seen before include "'Precision, exactness (8)'" , "Absolute correctness" , "faithfulness" , "Correctness - exactitude" , "precise" .)