1. A rate of inclination; a slope.
2. An ascending or descending part; an incline.
3. Physics. The rate at which a physical quantity, such as temperature or pressure, increases or decreases relative to change in a given variable, especially distance.
4. Mathematics. A vector having coordinate components that are the partial derivatives of a function with respect to its variables.
5. Biology. A series of progressively increasing or decreasing differences in the growth rate, metabolism, or physiological activity of a cell, organ, or organism.

[Perhaps GRADE + -ient, as in QUOTIENT.]

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.