Fit; competent (4)
I believe the answer is:
able
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">fit</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ >'<span class="explanation-format__original">competent</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ ></span>
(Other definitions for able that I've seen before include "Adept" , "Having great proficiency or intelligence" , "Competent as seaman may be" , "Practised" , "Having the necessary capacity (to do something)" .)