1. In gypsumboard joints, a slight concave depression in the joint treatment usually due to using too thin a mix of joint compound; also called a Starved Joint. 2. The decrease in volume, or contraction, of a material by the escape of any volatile substance, or by a chemical or physical change in the material. 3. Decrease in volume on drying. 4. Loss of bulk of soil when compacted in a fill; usually is computed on the basis of bank measure.