Gemini (5)
I believe the answer is:
twins
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">gemini</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know this)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for twins that I've seen before include "Two offspring born at the same time to the same mother" , "Two born together" , "Gemini" , "Sign" , "Matching pairs" .)