roughness vs surface

roughness

noun
  • Something that is rough; a rough spot. 

  • A measure of how rough something is, such as a surface 

  • Abundance, especially of food. 

  • Roughage; coarse fodder. 

  • The property of being rough, coarseness. 

surface

noun
  • The outside hull of a tangible object. 

  • Outward or external appearance. 

  • The overside or up-side of a flat object such as a table, or of a liquid. 

  • The locus of an equation (especially one with exactly two degrees of freedom) in a more-than-two-dimensional space. 

verb
  • To apply a surface to something. 

  • To make (information or facts) known. 

  • To become known or apparent; to appear or be found. 

  • To provide something with a surface. 

  • To bring to the surface. 

  • To come out of hiding. 

  • To work a mine near the surface. 

  • To rise to the surface. 

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