correspondence in WordNet English dictionary

1. compatibility of observations
   "there was no agreement between theory and measurement"; "the results of two tests were in correspondence"
   agreement  correspondence 
   
2. (mathematics) an attribute of a shape or relation; exact reflection of form on opposite sides of a dividing line or plane
   symmetry  symmetricalness  correspondence  balance 
   
3. the relation of corresponding in degree or size or amount
   commensurateness  correspondence  proportionateness 
   
4. similarity by virtue of corresponding
   parallelism  correspondence 
   
5. communication by the exchange of letters
   correspondence