Trusted adviser (6)
I believe the answer is:
mentor
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">trusted adviser</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 mentor that I've seen before include "Coach" , "Wise and trusted guide and advisor" , "One who steers" , "Train" , "One guiding" .)