controllable vs erratic

controllable

noun
  • Any factor that can be controlled. 

adj
  • Able to be controlled; subject to regulation or command. 

erratic

noun
  • A rock moved from one location to another, usually by a glacier. 

  • Anything that has erratic characteristics. 

adj
  • Deviating from normal opinions or actions; eccentric; odd. 

  • Unsteady, random; prone to unexpected changes; not consistent. 

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