American dated old stylish, wealthy person too
I believe the answer is:
as well
'too' is the definition.
('as well' can be a synonym of 'too')
'american dated old stylish wealthy person' is the wordplay.
I cannot quite understand how this works, but
'american' could be 'a' (common abbreviation - e.g. in organisation names) and 'a' is found in the answer.
'person' could be 'swell' (swell is a kind of person) and 'swell' is found within the answer.
No letters remain.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for as well that I've seen before include "Also, additionally" , "on top" , "Also, in addition" , "A swell sort of addition" , "with equal effect" .)