stratification

noun6

1. •
   The process leading to the formation or deposition of layers, especially of sedimentary rocks.
2. •
   Society's categorization of people into socioeconomic strata.
3. •
   A classification or arrangement of things into different categories or groups.
4. •
   A layering of musical texture.
5. •
   The vertical layering of vegetation in a forest.
6. •
   The process of treating seeds to simulate natural conditions that the seeds must experience before germination can occur, often involving exposure to cold.