Emily Dickinson Lexicon

LAC, n. [Sp. laca; G. lack; Dan. D. lak; said to be from the Arabic.]

A resinous substance produced mainly upon the Ficus Indica or Banyan tree, by the Coccus Ficus or Coccus Lacca. It is composed of five different varieties of resin, with a small quantity of several other substances, particularly a red coloring matter. Stick lac is the substance in its natural state, encrusting small twigs. When broken off and boiled in water, it loses its red color, and is called seed lac. When melted and reduced to a thin crust, it is called shell lac. United with ivory black or vermilion, it forms black and red sealing wax. Lac dissolved in alcohol or other menstrua, by different methods of preparation, constitutes various kinds of varnishes and lackers. – Thomson.