Ancient Aegean region (5)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">ancient aegean region</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 ionia that I've seen before include "East coast of the Aegean in Classical times" , "ancient region of Eastern Mediterranean" , "Classical Aegean region" , "Ancient area" , "Ancient Greek region" .)