convergence

Concise Oxford English Dictionary © 2008 Oxford University Press:
convergent/kənˈvɜːʤənt/

▶adjective

• 1 coming closer together; converging.

• 2 Biology (of unrelated animals and plants) showing a tendency to evolve superficially similar characteristics under similar environmental conditions.

• 3 Psychology (of thought) tending to follow well-established patterns.

– derivatives
convergence noun,
convergency noun.