exertive vs rapid

exertive

adj
  • Having power or a tendency to exert; using exertion. 

rapid

noun
  • a rough section of a river or stream which is difficult to navigate due to the swift and turbulent motion of the water. 

adj
  • Violent, severe. 

  • Needing only a brief exposure time. (of a lens, plate, film, etc.) 

  • Very swift or quick. 

  • Steep, changing altitude quickly. (of a slope) 

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