Transport hub (7)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">transport hub</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for airport that I've seen before include "Place for planes" , "passenger terminal" , "Aerodrome" , "See 18" , "... [GAULLISM] its founder perhaps" .)