Conjecture, theorise (9)
I believe the answer is:
speculate
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">conjecture</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I know that conjecture can be written as speculate)</span><br/ ><br/ >'<span class="explanation-format__original">theorise</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that theorise can be written as speculate)</span><br/ ><br/ ></span>
(Other definitions for speculate that I've seen before include "Guess without knowing the facts" , "Play the market" , "Imagine" , "Bet; theorise" , "Buy in hope of profit, but with risk of loss" .)