The Collaborative International Dictionary of English v.0.48:
Relatedness \Re*lat"ed*ness\, n. The state or condition of being related; relationship; affinity. [R.] --Emerson. [1913 Webster]WordNet (r) 3.0 (2006):
relatedness n 1: a particular manner of connectedness; "the relatedness of all living things" [ant: unrelatedness]