250. Convexity -- N. convexity, prominence, projection, swelling, gibbosity , bilge, bulge, protuberance, protrusion; camber, cahot [U.S.] .
252. Concavity -- N. concavity, depression, dip; hollow, hollowness; indentation, intaglio, cavity, dent, dint, dimple, follicle, pit, sinus, alveolus , lacuna; excavation, strip mine; trough &c (furrow) 259; honeycomb.
252a Sponge -- N. sponge, honeycomb, network; frit [Chem] , filter.
253. Sharpness -- N. sharpness &c adj.; acuity, acumination ; spinosity .
254. Bluntness -- N. bluntness &c adj..
255. Smoothness -- N. smoothness &c adj.; polish, gloss; lubricity, lubrication.
256. Roughness -- N. roughness &c adj.; tooth, grain, texture, ripple; asperity, rugosity , salebrosity , corrugation, nodosity ; arborescence &c 242; pilosity .
257. Notch -- N. notch, dent, nick, cut; indent, indentation; dimple.
258. Fold -- N. fold, plicature , plait, pleat, ply, crease; tuck, gather; flexion, flexure, joint, elbow, double, doubling, duplicature , gather, wrinkle, rimple , crinkle, crankle , crumple, rumple, rivel , ruck , ruffle, dog's ear, corrugation, frounce , flounce, lapel; pucker, crow's feet; plication .
259. Furrow -- N. furrow, groove, rut, sulcus [Anat.] , scratch, streak, striae, crack, score, incision, slit; chamfer, fluting; corduroy road, cradle hole.
260. Opening -- N. hole, foramen; puncture, perforation; fontanel ; transforation ; pinhole, keyhole, loophole, porthole, peephole, mousehole, pigeonhole; eye of a needle; eyelet; slot.
261. Closure -- N. closure, occlusion, blockade; shutting up &c v.; obstruction &c (hindrance) 706; embolus; contraction &c 195; infarction; constipation, obstipation ; blind alley, blind corner; keddah ; cul-de-sac, caecum; imperforation , imperviousness &c adj.; impermeability; stopper &c 263.
262. Perforator -- N. perforator, piercer, borer, auger, chisel, gimlet, stylet , drill, wimble , awl, bradawl, scoop, terrier, corkscrew, dibble, trocar [Med.] , trepan, probe, bodkin, needle, stiletto, rimer, warder, lancet; punch, puncheon; spikebit , gouge; spear &c (weapon) 727; puncher; punching machine, punching press; punch pliers.
263. Stopper -- N. stopper, stopple; plug, cork, bung, spike, spill, stopcock, tap; rammer ; ram, ramrod; piston; stop-gap; wadding, stuffing, padding, stopping, dossil , pledget , tompion , tourniquet.