(graphic arts) A layer of paint that is intended to be seen through a subsequent paint layer; an underpainted section of red, for example, can be altered to a violet or purple color with the application of a thin blue glaze.

McGraw-Hill Dictionary of Scientific and Technical Terms. Copyright © 2003, 1994, 1989, 1984, 1978, 1976, 1974 by McGraw-Hill Companies, Inc. All rights reserved.