a hard, brittle, translucent, and commonly transparent substance, white or colored, having a conchoidal fracture, and made by fusing together sand or silica with lime, potash, soda, or lead oxide. it is used for window panes and mirrors, for articles of table and culinary use, for lenses, and various articles of ornament.-any substance having a peculiar glassy appearance, and a conchoidal fracture, and usually produced by fusion.-anything made of glass.-a looking-glass; a mirror.-a vessel filled with running sand for measuring time; an hourglass; and hence, the time in which such a vessel is exhausted of its sand.-a drinking vessel; a tumbler; a goblet; hence, the contents of such a vessel; especially; spirituous liquors; as, he took a glass at dinner.-an optical glass; a lens; a spyglass; -- in the plural, spectacles; as, a pair of glasses; he wears glasses.-a weatherglass; a barometer.-to reflect, as in a mirror; to mirror; -- used reflexively.-to case in glass.-to cover or furnish with glass; to glaze.-to smooth or polish anything, as leater, by rubbing it with a glass burnisher.