correspondence
ˌkär-
Noun
1
a
: communication by letters or email
also : the letters or emails exchanged
I have a pile of correspondence on my desk.
b
: the news, information, or opinion contributed by a correspondent to a newspaper or periodical
2
a
: the agreement of things with one another
the correspondence between spelling and pronunciation
b
: a particular similarity
c
: a relation between sets in which each member of one set is associated with one or more members of the other
Source