1. n. [Geology]

A layer of sedimentary rock. The plural form is strata.

See: angular unconformity,  bed,  bed thickness,  chronostratigraphic chart,  chronostratigraphy,  competent,  conformable,  conformable,  correlate,  disconformity,  formation,  hiatus,  incompetent,  lamination,  nonconformity,  normal fault,  paleontology,  parasequence,  rock,  sedimentary,  sequence,  sequence stratigraphy,  stratigraphy,  superposition,  unconformity