Old World finch (6)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">old world finch</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for linnet that I've seen before include "See three down" , "Finch formerly popular as a pet" , "Brown-gray kind of finch" , "Member of finch family" , "Songster" .)