N layer, stratum, strata, course, bed, zone, substratum, substrata, floor, flag, stage, story, tier, slab, escarpment, table, tablet, dess, flagstone, board, plank, trencher, platter, plate, lamina, lamella, sheet, foil, wafer, scale, flake, peel, coat, pellicle, membrane, film, leaf, slice, shive, cut, rasher, shaving, integument, eschar, stratification, scaliness, nest of boxes, coats of an onion, monolayer, bilayer, trilayer, lamellar, lamellated, lamelliform, layered, laminated, laminiferous, micaceous, schistose, schistous, scaly, filmy, membranous, pellicular, flaky, squamous, foliated, foliaceous, stratified, stratiform, tabular, discoid, spathic, spathose, trilamellar, graphitic.

Exteriority

N exteriority, outside, exterior, surface, superficies, skin, superstratum, disk, disc, face, facet, extrados, excentricity, eccentricity, circumjacence, exterior, external, outer most, outward, outlying, outside, outdoor, round about, extramural, extralimitary, extramundane, superficial, skin-deep, frontal, discoid, extraregarding, excentric, eccentric, outstanding, extrinsic, ecdemic, exomorphic, externally, out, with out, over, outwards, ab extra, out of doors, extra muros, in the open air, sub Jove, sub dio, a la belle etoile, al fresco.

Flatness

N flatness, smoothness, plane, level, plate, platter, table, tablet, slab, flat, plane, even, flush, scutiform, discoid, level, flat as a pancake, flat as a fluke, flat as a flounder, flat as a board, flat as my hand.

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