A hard glossy coating WordNet 3.0 & Open English WordNet

Lacquer is a type of hard and usually shiny coating or finish applied to materials such as wood or metal. Wikipedia

Liquid or powder coating material which is applied thinly to objects to form a hard finish Wikidata

A material which contains a substantial quantity of a cellulose derivative, most commonly nitrocellulose but sometimes a cellulose ester, such as cellulose acetate or cellulose butyrate, or a cellulose ether such as ethyl cellulose; used to give a glossy finish, especially on brass and other bright metals. OmegaWiki