convergence

 
(also convergency)

noun

[mass noun]
  • the process or state of converging: the convergence of lines in the distance
  • Biology the tendency of unrelated animals and plants to evolve superficially similar characteristics under similar environmental conditions: these bivalves have assumed similar characters by convergence
  • (also convergence zone) a location where airflows or ocean currents meet, characteristically marked by upwelling (of air) or downwelling (of water).