Oh dear, stupid husband departing capital could be George Bush (9)
I believe the answer is:
aerodrome
'departing capital could be george bush' is the definition.
I can't tell whether this defines the answer.
'oh dear stupid husband' is the wordplay.
'oh' becomes 'o'.
'stupid' indicates anagramming the letters (in a stupid order).
'husband' becomes 'rome' (I can't justify this - if you can you should believe this answer much more).
'o'+'dear'='odear'
'odear' with letters rearranged gives 'aerod'.
'aerod'+'rome'='AERODROME'
Can you help me to learn more?
(Other definitions for aerodrome that I've seen before include "Point of arrival, perhaps" , "where flight may terminate" , "landing area" , "Small field" , "go here if flying" .)