1. engineering the rise or fall of a ground surface or of the line of a road, ditch, or other linear construction, expressed as one unit vertical to so many units horizontal (e.g., 1/20 or one in 20) or as a percent or degrees of slope —synonym gradient —note the slope at right angles to the line of a linear construction is termed the side grade 2. engineering the proportion and distribution of coarse, medium, and fine soil particles in relation to structural use 3. utilization an established quality or use classification of lumber, trees, or other forest productsThis definition last updated 10/27/2008