n. 1. The rate of regular or graded ascent or descent in a road; grade. [ 1913 Webster ] 2. A part of a road which slopes upward or downward; a portion of a way not level; a grade. [ 1913 Webster ] 3. The rate of increase or decrease of a variable magnitude, or the curve which represents it; as, a thermometric gradient. 4. (Chem., Biochem.) The variation of the concentration of a chemical substance in solution through some linear path; also called concentration gradient; -- usually measured in concentration units per unit distance. Concentration gradients are created naturally, e.g. by the diffusion of a substance from a point of high concentration toward regions of lower concentration within a body of liquid; in laboratory techniques they may be made artificially. [ PJC ] gradient maker (Biochem.) a device which creates a concentration gradient in a solution within some apparatus; -- used, e. g., for separation of biochemical substances. [ PJC ] Gradient post, a post or stake indicating by its height or by marks on it the grade of a railroad, highway, or embankment, etc., at that spot.
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