Blue-green shade (4)
I believe the answer is:
teal
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">blue</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I know that teal is a type of blue)</span><br/ ><br/ >'<span class="explanation-format__original">green shade</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ ></span>
(Other definitions for teal that I've seen before include "Duck - dark greenish-blue" , "Variety of duck" , "Duck; greenish-blue colour" , "Dark green-blue; duck" , "Dark greenish-blue colour" .)