What is "gradient post"

Gradient \Gra"di*ent\, n.

1. The rate of regular or graded ascent or descent in a road; grade.

2. A part of a road which slopes upward or downward; a portion of a way not level; a grade.

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.

   gradient maker (Biochem.) a device which creates a concentration gradient in a solution within some apparatus; -- used, e. g., for separation of biochemical substances.

   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.

n. A post or stake indicating by its height or by marks on it the grade of a railroad, highway, embankment, etc. at that point.