The Collaborative International Dictionary of English v.0.48:

Contiguity \Con`ti*gu"i*ty\, n. [Cf. F. contiguit['e], LL.
   contiguitas.]
   The state of being contiguous; intimate association;
   nearness; proximity.
   [1913 Webster]

         The convicinity and contiguity of the two parishes.
                                                  --T. Warton.
   [1913 Webster]

WordNet (r) 3.0 (2006):

contiguity
    n 1: the attribute of being so near as to be touching [syn:
         adjacency, contiguity, contiguousness]

Moby Thesaurus II by Grady Ward, 1.0:

58 Moby Thesaurus words for "contiguity":
   abutment, abuttal, accord, addition, adjacency, adjoiningness,
   adjunct, affairs, affiliation, affinity, alliance, apposition,
   approximation, appulse, assemblage, association, bond, closeness,
   combination, conjugation, conjunction, connectedness, connection,
   conterminousness, contiguousness, contrariety, coterminousness,
   dealings, deduction, disjunction, filiation, homology, immediacy,
   intercourse, intimacy, junction, juxtaposition, liaison, link,
   linkage, linking, mutual attraction, nearness, perigee, perihelion,
   propinquity, proximity, rapport, relatedness, relation, relations,
   relationship, similarity, sympathy, syzygy, tie, tie-in, union