inclination vs upslope

inclination

noun

  • A slant or slope. 

  • A tendency. 

  • The angle of intersection of a reference plane 

  • A physical tilt or bend. 

upslope

noun

  • an upward slope 

adv

  • up a slope 

adj

  • in a direction up a slope 

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