Varnish

n. surface coat (usually of paint) which glazes and protects; solution which provides a glossy or protective coating, lacquer; superficially polished appearance

v. cover with a protective (often glossy) coating; give something a superficially polished appearance

Varnish is a transparent, hard, protective finish or film primarily used in wood finishing but also for other materials. Varnish is traditionally a combination of a drying oil, a resin, and a thinner or solvent. Varnish finishes are usually glossy but may be designed to produce satin or semi-gloss sheens by the addition of "flatting" agents. Varnish has little or no color, is transparent, and has no added pigment, as opposed to paints or wood stains, which contain pigment and generally range from opaque to  translucent. Varnishes are also applied over wood stains as a final step to achieve a film for gloss and protection. Some products are marketed as a combined stain and varnish.
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Noun
1. paint that provides a hard glossy transparent coating
(hypernym) paint
(hyponym) fixative
(derivation) seal
Verb
1. cover with varnish
(synonym) seal
(hypernym) coat, surface
(hyponym) shellac
(derivation) varnisher

(n.)
To lay varnish on; to cover with a liquid which produces, when dry, a hard, glossy surface; as, to varnish a table; to varnish a painting.
  

(n.)
To cover or conceal with something that gives a fair appearance; to give a fair coloring to by words; to gloss over; to palliate; as, to varnish guilt.
  

(n.)
That which resembles varnish, either naturally or artificially; a glossy appearance.
  

(n.)
An artificial covering to give a fair appearance to any act or conduct; outside show; gloss.
  

(n.)
A viscid liquid, consisting of a solution of resinous matter in an oil or a volatile liquid, laid on work with a brush, or otherwise. When applied the varnish soon dries, either by evaporation or chemical action, and the resinous part forms thus a smooth, hard surface, with a beautiful gloss, capable of resisting, to a greater or less degree, the influences of air and moisture.
  

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