the widely accepted theory that an individual animal or plant develops by the gradual differentiation and elaboration of a fertilized egg cell
Compare preformation (sense 2)
2.
the formation or alteration of rocks after the surrounding rock has been formed
3.
alteration of the mineral composition of a rock by external agents: a type of metamorphism
Derived forms
epigenesist (ˌepiˈgenesist) or epigenist (ɪˈpɪdʒɪnɪst)
noun
epigenesis in American English
(ˌɛpɪˈdʒɛnəsɪs)
noun
1. Biology
the theory that the embryo, influenced by its internal and external environment, develops progressively by stages, forming structures that were not originally present in the egg
see also preformation
2. Geology
a type of metamorphism in which the mineral content of a rock changes as a result of external influences