Have the hump when touring rotten, backward county (7)
I believe the answer is:
suffolk
'county' is the definition.
(I know that Suffolk is a county)
'have the hump when touring rotten backward' is the wordplay.
'have the hump' becomes 'sulk' (I can't justify this - if you can you should give a lot more credence to this answer).
'when touring' means one lot of letters goes inside another.
'rotten' becomes 'off' (rotten food is 'off').
'backward' says the letters should be written backwards.
'off' reversed gives 'ffo'.
'sulk' placed around 'ffo' is 'SUFFOLK'.
Can you help me to learn more?
(Other definitions for suffolk that I've seen before include "Ipswich's county" , "English county" , "East Anglian county" , "Eastern county" , "sheep" .)