80 euros for starter in café? That's out of order (9)
I believe the answer is:
fourscore
'80' is the definition.
('fourscore' can be a synonym of '80')
'euros for starter in cafe? that's out of order' is the wordplay.
I cannot really see how this works, but
'euros' could be 'e' and 'e' is present in the answer.
'that's' could be 'sc' and 'sc' is found within the answer.
'of' could be 'o' and 'o' is found in the answer.
'order' could be 'o' (abbreviation e.g. in British honours OM, OBE etc.) and 'o' is found within the answer.
This may be the basis of clue (or it may be nonsense).
(Other definitions for fourscore that I've seen before include "number" , "Eighty" , "''... and seven years ago, our fathers.... (Gettysburg address)" .)