O, annular muscle, annulus, areola, aureole, carousel, chaplet, circle, circuit, circumference, circus, closed circle, coat, coating, collop, corona, coronet, covering, crown, cut, cycle, deal, diadem, discus, eternal return, fairy ring, feuille, film, flap, foil, fold, garland, glory, halo, lamella, lamina, laminated glass, laminated wood, lap, lasso, leaf, logical circle, loop, looplet, magic circle, membrane, merry-go-round, noose, orbit, pane, panel, patina, peel, pellicle, plait, plank, plate, plating, ply, plywood, radius, rasher, ring, roller, rolling stone, rondelle, rotator, rotor, round, roundabout, roundel, rundle, safety glass, saucer, scum, sheet, skin, slab, slat, slice, sphincter, table, tablet, top, veneer, vicious circle, wafer, wheel, whirlabout, whirler, whirligig, wreath