noun
( -s )
Etymology: from gerund of flash (I)
1. : the reheating of an article of glass at the furnace aperture to restore its plastic condition ; especially : the reheating of a globe of crown glass to allow it to flash
2. : strips of sheet metal (as copper or galvanized iron) bent to fit in the interior angle between a wall and a roof surface or in the valley between two intersecting roof surfaces in order to make a watertight joint — compare counterflashing , filleting
3. : a lap joint (as a bell-and-spigot joint) in plumber's leadwork
4. : the small-stop exposure to white paper of the photographic emulsion as a preliminary step in making a halftone