Railway employee (9)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">railway employee</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 signalman that I've seen before include "Rail worker" , "Main slang (anag.)" , "one controlling traffic movement" , "Railway employee controlling points" , "Railway worker" .)