gradient vs shilling mark

gradient

noun
  • A rate of inclination or declination of a slope. 

  • 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. 

  • A slope or incline. 

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

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

  • Moving by steps; walking. 

  • Rising or descending by regular degrees of inclination. 

shilling mark

noun
  • Synonym of slash ⟨/⟩ in its use to mark the amount of shillings in a sum or (obsolete) in all its uses. 

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