Travel hub (7)
'travel hub' is the definition.
(a centre for air travel)
This is the entire clue.
(Other definitions for airport that I've seen before include "eg Stansted" , "landing here?" , "Terminal for planes" , "Fliers' terminus" , "Destination for planes" .)
(Other definitions for coach station that I've seen before include "Depot" , "Stop" .)