interfluous

from The Collaborative International Dictionary of English v.0.48

Interfluent \In*ter"flu*ent\, Interfluous \In*ter"flu*ous\, a.
   [L. interfluens, p. pr., and interfluus. See {Inter-}, and
   {Fluent}.]
   Flowing between or among; intervening. --Boyle.
   [1913 Webster]