Appleton layer, F layer, Heaviside-Kennelly layer, Van Allen belt, band, bed, bedding, belt, blood, bracket, branch, caste, category, chemosphere, clan, class, couche, course, deck, division, estate, floor, gallery, grade, group, grouping, head, heading, ionosphere, isothermal region, kin, label, layer, ledge, level, lower atmosphere, measures, order, outer atmosphere, overlayer, overstory, photosphere, pigeonhole, plane, position, predicament, race, rank, rating, rubric, seam, section, sept, set, shelf, stage, standing, station, status, step, story, strain, stratification, stratosphere, subdivision, subgroup, suborder, substratosphere, substratum, superstratum, table, thickness, tier, title, topsoil, tropopause, troposphere, underlayer, understory, understratum, upper atmosphere, vein, zone