GRADE (Slope)

1. The slope or rate of incline of a road or surface, expressed as a percentage or a ratio. Also read the article SLOPE, DEFINITION AND HOW TO CALCULATE.
2. Ground level, or the elevation at any given point.
3. The work of leveling dirt.
4. The designated quality of a manufactured piece of wood. 

EXAMPLE: 

A 7% grade is more steep than a 4% grade.