Word Study
opal
CIDE DICTIONARY
opal, n. [L. opalus: cf. Gr. , Skr. upala a rock, stone, precious stone: cf. F. opale.].
A mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity. [1913 Webster]
" The precious opal presents a peculiar play of colors of delicate tints, and is highly esteemed as a gem. One kind, with a varied play of color in a reddish ground, is called the harlequin opal . The fire opal has colors like the red and yellow of flame. Common opal has a milky appearance. Menilite is a brown impure variety, occurring in concretions at Menilmontant, near Paris. Other varieties are cacholong , girasol , hyalite , and geyserite ." [1913 Webster]
OXFORD DICTIONARY
opal, n. a quartzlike form of hydrated silica, usu. white or colourless and sometimes showing changing colours, often used as a gemstone.
Idiom
opal glass a semi-translucent white glass.
Etymology
F opale or L opalus prob. ult. f. Skr. upalas precious stone
ROGET THESAURUS
opal
Jewelry
N jewel, jewelry, jewellery, bijoutry, bijou, bijouterie, trinket, fine jewelry, costume jewelry, junk jewelry, gem, gemstone, precious stone, necklace, bracelet, anklet, earring, locket, pendant, charm bracelet, ring, pinky ring, carcanet, chain, chatelaine, broach, pin, lapel pin, torque, diamond, brilliant, rock, beryl, emerald, chalcedony, agate, heliotrope, girasol, girasole, onyx, plasma, sard, sardonyx, garnet, lapis lazuli, opal, peridot, tourmaline, chrysolite, sapphire, ruby, synthetic ruby, spinel, spinelle, balais, oriental, oriental topaz, turquois, turquoise, zircon, cubic zirconia, jacinth, hyacinth, carbuncle, amethyst, alexandrite, cat's eye, bloodstone, hematite, jasper, moonstone, sunstone, pearl, cultured pearl, fresh-water pearl, mother of pearl, coral, jeweler, gemologist, minerologist, lapidary, lapidarian, gemology, gemmology, minerology, bejeweled, diamond, (gemstones), gemological.Semitransparency
N semitransparency, translucency, semiopacity, opalescence, milkiness, pearliness, gauze, muslin, film, mica, mother-of-pearl, nacre, mist, opal, turbidity, Adj, semitransparent, translucent, semipellucid, semidiaphanous, semiopacous, semiopaque, opalescent, opaline, pearly, milky, frosted, nacreous, semitransparent, translucent, semipellucid, semidiaphanous, semiopacous, semiopaque, opalescent, opaline, pearly, milky, frosted, nacreous, V, opalesce, (ii) SPECIFIC LIGHT.Variegation
N variegation, colors, dichroism, trichroism, iridescence, play of colors, polychrome, maculation, spottiness, striae, spectrum, rainbow, iris, tulip, peacock, chameleon, butterfly, tortoise shell, mackerel, mackerel sky, zebra, leopard, cheetah, nacre, ocelot, ophite, mother-of-pearl, opal, marble, check, plaid, tartan, patchwork, marquetry-, parquetry, mosaic, tesserae, strigae, chessboard, checkers, chequers, harlequin, Joseph's coat, tricolor, variegated, many-colored, many-hued, divers-colored, party- colored, dichromatic, polychromatic, bicolor, tricolor, versicolor, of all the colors of the rainbow, of all manner of colors, kaleidoscopic, iridescent, opaline, opalescent, prismatic, nacreous, pearly, shot, gorge de pigeon, chatoyant, irisated, pavonine, pied, piebald, motley, mottled, marbled, pepper and salt, paned, dappled, clouded, cymophanous, mosaic, tesselated, plaid, tortoise shell, spotted, spotty, punctated, powdered, speckled, freckled, flea-bitten, studded, flecked, fleckered, striated, barred, veined, brinded, brindled, tabby, watered, grizzled, listed, embroidered, daedal, naevose, stipiform, strigose, striolate, (iii) PERCEPTIONS OF LIGHT.For further exploring for "opal" in Webster Dictionary Online