Thus, therefore (4)
I believe the answer is:
ergo
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">thus</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >'<span class="explanation-format__original">therefore</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 ergo that I've seen before include "'Therefore, to the old Romans (4)'" , "Consequently" , "as a consequence" , "'Cogito, ---- sum'" , "for this reason" .)