Support for Portugal (4)
I believe the answer is:
prop
'support' is the definition.
(prop is a kind of support)
'for portugal' is the wordplay.
'for' becomes 'pro' (as in being 'pro' something).
'portugal' becomes 'p' (common abbreviation eg on car number plates).
'pro'+'p'='PROP'
(Other definitions for prop that I've seen before include "Temporary support" , "See 5" , "A rigid supprot or piece of satge furniture (4)" , "Hold (up), support" , "Person or thing providing support" .)