gra·di·ent (gr??d?-?nt)n. Abbr. grad.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, changes in response to changes 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).]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.gradient (??re?d??nt) n1. (Civil Engineering) Also called (esp US): grade a part of a railway, road, etc, that slopes upwards or downwards; inclination2. (Civil Engineering) Also called (esp US and Canadian): grade a measure of such a slope, esp the ratio of the vertical distance between two points on the slope to the horizontal distance between them3. (General Physics) physics a measure of the change of some physical quantity, such as temperature or electric potential, over a specified distance4. (Mathematics) maths a. (of a curve) the slope of the tangent at any point on a curve with respect to the horizontal axisb. (of a function, f(x, y, z)) the vector whose components along the axes are the partial derivatives of the function with respect to each variable, and whose direction is that in which the derivative of the function has its maximum value. Usually written: grad f, ?f or ?f. Compare curl11, divergence4adjsloping uniformly[C19: from Latin gradi?ns stepping, from grad? to go]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014gra?di?ent (?gre? di ?nt) n. 1. the degree of inclination of a highway, railroad, etc., or the rate of ascent or descent of a stream or river. 2. an inclined surface; grade; ramp. 3. a. the rate of change with respect to distance of a variable quantity, as temperature or pressure, in the direction of maximum change. b. a curve representing such a rate of change. 4. a differential operator that, operating upon a function of several variables, results in a vector whose coordinates are the partial derivatives of the function. Abbr.: grad. Symbol:? adj. 5. rising or descending by regular degrees of inclination. 6. progressing by walking; stepping with the feet as animals do. [1635?45;