The Collaborative International Dictionary of English v.0.48:
Centrality \Cen*tral"i*ty\, n.; pl. Centralities. The state of being central; tendency towards a center. [1913 Webster] Meantime there is a great centrality, a centripetence equal to the centrifugence. --R. W. Emerson. [1913 Webster]WordNet (r) 3.0 (2006):
centrality n 1: the property of being central [ant: marginality]