The Collaborative International Dictionary of English v.0.48:

Freemasonry \Free"ma`son*ry\, n.
   The institutions or the practices of freemasons.
   [1913 Webster]

WordNet (r) 3.0 (2006):

freemasonry
    n 1: a natural or instinctive fellowship between people of
         similar interests; "he enjoyed the freemasonry of the
         Press"
    2: Freemasons collectively [syn: Freemasonry, Masonry]

Moby Thesaurus II by Grady Ward, 1.0:

49 Moby Thesaurus words for "freemasonry":
   affiliation, alignment, alliance, amalgamation, association,
   boon companionship, brotherhood, brotherliness, cahoots, chumship,
   coadunation, coalescence, coalition, colleagueship, collegialism,
   collegiality, combination, community of interest, companionship,
   comradeship, confederacy, confederation, confraternity,
   consolidation, consortship, copartnership, copartnery,
   esprit de corps, federation, fellowship, fraternalism, fraternity,
   fraternization, fusion, hookup, inclusion, incorporation,
   integration, league, merger, partnership, sisterhood, sisterliness,
   sodality, sorority, tie-in, tie-up, unification, union