Non-verbal communication (6)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">non-verbal communication</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for signal that I've seen before include "Indication; a train control" , "important to train drivers > striking" , "Gesture with meaning" , "Indicate" , "Aligns (anag) -- gesture" .)
(Other definitions for body language that I've seen before include "Unspoken communication" , "suggestive poses?" , "Non-verbal communication by posture, gestures etc" , "Reading material" , "means of communication?" .)