The Collaborative International Dictionary of English v.0.48:

Neighborly \Neigh"bor*ly\, a. [Also written neighbourly.]
   Appropriate to the relation of neighbors; having frequent or
   familiar intercourse; kind; civil; social; friendly. -- adv.
   In a neighborly manner.
   [1913 Webster]

         Judge if this be neighborly dealing.     --Arbuthnot.
   [1913 Webster]

WordNet (r) 3.0 (2006):

neighborly
    adj 1: exhibiting the qualities expected in a friendly neighbor
           [syn: neighborly, neighbourly]