Western Samoa's capital
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">western samoa's capital</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for apia that I've seen before include "Samoan port" , "Capital of Samoa" , "Pacific capital" .)