The Collaborative International Dictionary of English v.0.48:

Forgather \For*gath"er\, v. i.
   To convene; to gossip; to meet accidentally. [Scot.]
   --Jamieson.
   [1913 Webster]

         Within that circle he forgathered with many a fool.
                                                  --Wilson.
   [1913 Webster]

WordNet (r) 3.0 (2006):

forgather
    v 1: collect in one place; "We assembled in the church
         basement"; "Let's gather in the dining room" [syn: meet,
         gather, assemble, forgather, foregather]

Moby Thesaurus II by Grady Ward, 1.0:

42 Moby Thesaurus words for "forgather":
   assemble, bunch, bunch up, clot, cluster, collect, come together,
   congregate, congress, converge, copulate, couple, crowd, date,
   flock together, flow together, fuse, gang around, gang up, gather,
   gather around, herd together, hive, horde, huddle, league, link,
   mass, meet, merge, mill, muster, raise, rally, rally around,
   rendezvous, seethe, stream, surge, swarm, throng, unite