Detection device (6)
I believe the answer is:
sensor
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">detection device</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for sensor that I've seen before include "A furtive look" , "Device that reacts to stimulus from snores" , "One detects" , "device to detect change?" , "Detecting device" .)