pearl

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A smooth, lustrous, variously colored mass, chiefly of calcium carbonate, formed around a grain of sand or other foreign matter inside the shell of certain bivalve mollusks and valued as a gem.
• noun A bead resembling one of these masses.
• noun Mother-of-pearl; nacre.
• noun One that is highly regarded for its beauty or value.
• noun Printing A type size measuring approximately five points.
• noun A yellowish white.
• intransitive verb To decorate or cover with pearls or beads resembling pearls.
• intransitive verb To make into the shape or color of pearls.
• intransitive verb To dive or fish for pearls or pearl-bearing mollusks.
• intransitive verb To form beads resembling pearls.

from The Century Dictionary.

• noun In ship-rigging, one of the bull's-eye rollers strung on the round iron band which spans the forward part of the gaff on fore-and-aft vessels, and which assist in the smooth hoisting of the spar, as well as confining it to the mast.
• To adorn, set, or stud with pearls.
• To make into a form, or to cause to assume an appearance, resembling that of pearls: as, to pearl barley (by rubbing off the pulp and grinding the berries to a rounded shape); to pearl comfits (by causing melted sugar to harden around the kernels, thus forming small rounded pellets).
• To resemble pearls.
• To take a rounded form, as a drop of liquid: as, quicksilver pearls when dropped in small quantities.
• To assume a resemblance to pearls, or the shape of pearls, as barley or comfits.
• noun A nacreous concretion, or separate mass of nacre, of hard, smooth, lustrous texture, and a rounded, oval, pear-shaped, or irregular figure, secreted within the shells of various bivalve mollusks as a result of the irritation caused by the presence of some foreign body, as a grain of sand, within the mantle-lobes.
• noun Anything very valuable; the choicest or best part; a jewel; the finest of its kind.
• noun Something round and clear, as a drop of water or dew; any small granule or globule resembling a pearl; specifically, in pharmacy, a small pill or pellet containing or consisting of some medicinal substance.
• noun A white speck or film growing on the eye; cataract.
• noun Mother-of-pearl; nacre: as, a pearl button.
• noun A size of printing-type, about 15 lines to the inch, intermediate between the larger size agate and the smaller size diamond: it is equal to 5 points, and is so distinguished in the new system of sizes.
• noun This line is printed in pearl.
• noun In heraldry: A small ball argent, not only as a bearing but as part of a coronet.
• noun The color white.
• noun One of the bony tubercles which form a rough circle round the base of a deer's antler, called collectively the bur.
• noun In entomology, a name of many pyralid moths; any pearl-moth.
• noun A fish, the prill or brill: perhaps so called from the light spots, otherwise probably a transposed form of prill.
• noun Eccles., a name sometimes given to a particle of the consecrated wafer: still current in the Oriental Church.
• noun A name given by gilders and manufacturers of jewelry to granules of metal produced by melting it to extreme fluidity, and then pouring it into cold water.
• noun In lace- and ribbon-making, one of the loops which form the outer edge. Also purl.
• noun In decorative art. See purl.

from the GNU version of the Collaborative International Dictionary of English.

• adjective Of or pertaining to pearl or pearls; made of pearls, or of mother-of-pearl.
• noun obsolete A fringe or border.
• noun See Purl stitch, under Purl.
• transitive verb To set or adorn with pearls, or with mother-of-pearl. Used also figuratively.
• transitive verb To cause to resemble pearls; to make into small round grains.
• intransitive verb To resemble pearl or pearls.
• intransitive verb To dive or hunt for pearls.
• noun (Zoöl.) A shelly concretion, usually rounded, and having a brilliant luster, with varying tints, found in the mantle, or between the mantle and shell, of certain bivalve mollusks, especially in the pearl oysters and river mussels, and sometimes in certain univalves. It is usually due to a secretion of shelly substance around some irritating foreign particle. Its substance is the same as nacre, or mother-of-pearl.
• noun Hence, figuratively, something resembling a pearl; something very precious.
• noun Nacre, or mother-of-pearl.
• noun (Zoöl.) A fish allied to the turbot; the brill.
• noun (Zoöl.) A light-colored tern.
• noun (Zoöl.) One of the circle of tubercles which form the bur on a deer's antler.
• noun obsolete A whitish speck or film on the eye.
• noun A capsule of gelatin or similar substance containing some liquid for medicinal application, as ether.
• noun (Print.) A size of type, between agate and diamond.