N inclosure, envelope, case, wrapper, girdle, pen, fold, pen fold, in fold, sheep fold, paddock, pound, corral, yard, net, seine net, wall, hedge, hedge row, espalier, fence, pale, paling, balustrade, rail, railing, quickset hedge, park paling, circumvallation, enceinte, ring fence, barrier, barricade, gate, gateway, bent, dingle, door, hatch, cordon, prison, dike, dyke, ditch, fosse, moat.

Concavity

N concavity, depression, dip, hollow, hollowness, indentation, intaglio, cavity, dent, dint, dimple, follicle, pit, sinus, alveolus, lacuna, excavation, strip mine, trough, honeycomb, cup, basin, crater, punch bowl, cell, socket, valley, vale, dale, dell, dingle, combe, bottom, slade, strath, glade, grove, glen, cave, cavern, cove, grot, grotto, alcove, cul-de- sac, gully, arch, bay, excavator, sapper, miner, honeycomb (sponge), depressed, alveolate, calathiform, cup-shaped, dishing, favaginous, faveolate, favose, scyphiform, scyphose, concave, hollow, stove in, retiring, retreating, cavernous, porous, infundibul, infundibular, infundibuliform, funnel shaped, bell shaped, campaniform, capsular, vaulted, arched.

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