White Monopoly bills (4)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">white monopoly bills</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for ones that I've seen before include "Aces" , "Units" , "Individuals" , "1 & 1 & 1" , "(Of ship) returning to port of origin" .)