[v] render fertile and preserve by placing between layers of earth or sand; "stratify seeds"
[v] form layers or strata; "The rock stratifies"
[v] form, arrange, or deposit in layers; "The fish are stratified in barrels"; "The rock was stratified by the force of the water"; "A statistician stratifies the list of names according to the addresses"
[v] divide society into social classes or castes; "Income distribution often stratifies a society"
[v] develop different social levels, classes, or castes; "Society stratifies when the income gap widens"