Tipster (4)
I believe the answer is:
tout
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">tipster</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for tout that I've seen before include "Pester people to buy, like race tipster" , "All in Paris" , "Try to sell in a direct manner" , "Profiting ticket seller" , "Solicit, canvass" .)