According to Conrad H. Waddington (1905-1975), this concept represents a general summary of a number of facts in genetics and embryology. Broadly speaking, it can be defined as the capacity of the epigenetic system to attain developmental end-states despite minor variations in initial conditions and conditions met during subsequent development (viz., genetic and environmental perturbations). The depth to which a developmental pathway is canalised or buffered is taken to represent the strength of its homeorhetic properties.
See Constraint, Determination, Equifinality, Epigenetic landscape, Epigenetics, Homeorhesis