Homeorhesis, derived from the Greek for "similar flow", is a concept encompassing dynamical systems which return to a trajectory, as opposed to systems which return to a particular state, which is termed homeostasis.
The word itself is a little-used term of art in biology, where it describes the tendency of developing or changing organisms to continue development or change towards a given state, even if disturbed in development.
The term was first coined by C.H. Waddington, on or before 1940, along with the related term chreod, meaning "necessary path", which is the trajectory to which the system tends to return.
In ecology the concept is important as an element of the Gaia theory, where the system under consideration is the ecological balance of different forms of life on the planet.