strat·i·fy / ˈstratəˌfī/ • v. (-fies, -fied) [tr.] [usu. as adj.] (stratified) form or arrange into strata: socially stratified cities | [intr.] the residues have begun to stratify. ∎ arrange or classify: stratifying patients into well-defined risk groups. ∎ place (seeds) close together in layers in moist sand or peat to preserve them or to help them germinate. ∎ [intr.] (of seeds) be germinated by this method.DERIVATIVES: strat·i·fi·ca·tion / ˌstratəfiˈkāshən/ n.