gradient vs upgrade

gradient

noun
  • A slope or incline. 

  • The ratio of the rates of change of a dependent variable and an independent variable, the slope of a curve's tangent. 

  • A differential operator that maps each point of a scalar field to a vector pointed in the direction of the greatest rate of change of the scalar. Notation for a scalar field φ: ∇φ 

  • A gradual change in color. A color gradient; gradation. 

  • The rate at which a physical quantity increases or decreases relative to change in a given variable, especially distance. 

  • A rate of inclination or declination of a slope. 

adj
  • Adapted for walking, as the feet of certain birds. 

  • Moving by steps; walking. 

  • Rising or descending by regular degrees of inclination. 

upgrade

noun
  • An upward grade or slope. 

  • An improvement 

  • An improved component or replacement item, usually applied to technology 

adv
  • Up a slope or grade. 

verb
  • To improve, usually applied to technology, generally by complete replacement of one or more components 

  • To replace with something better. 

  • To improve the equipment or furnishings of or services rendered to 

  • To replace a program with a later version of itself, a version having a higher version number or marketed under a more recent product name. 

  • To improve in condition or status. 

How often have the words gradient and upgrade occurred in a corpus of books? (source: Google Ngram Viewer )