A stratum is a layer of sedimentary rock or sediment. Stratum may also refer to: Science and technology Stratum (linguistics), a language influencing or influenced through language contact Stratum (statistics), in stratified sampling, a homogeneous subgroup of members in the population Stratum, an element of a topologically stratified space Clock stratum, in a clock network, a hierarchical level reflecting the quality of a clock Other uses Stratum, Netherlands, a city district of Eindhoven Stratum (album), a 2012 album by Drottnar Stratum (sculpture), a series of sculptures by Mikyoung Kim in Portland, Oregon, US See also Strata (disambiguation) Stratification (disambiguation) Substrate (disambiguation) Superstrate