Dense; agreement (7)
I believe the answer is:
compact
I believe this is a double definition.
'dense' is the first definition.
(similar in meaning)
'agreement' is the second definition.
(compact can mean an agreement)
(Other definitions for compact that I've seen before include "The powder-box is closely packed" , "Mutual agreement" , "it could be in the bag" , "Dense; formal contract" , "Dense; agreement" .)