A good deal of the area of France (3)
I believe the answer is:
lot
'a good deal' is the definition.
(synonyms)
'of the area of france' is the wordplay.
I cannot really understand how this works, but
'of' could be 'o' and 'o' is located in the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is located in the answer.
A single letter 'l' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for lot that I've seen before include "Abraham's nephew (OT)" , "Destiny - auction item(s)" , "His Biblical wife was turned to a pillar of salt" , "A person's luck" , "Share - tons" .)