erratic vs systematic

erratic

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

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

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

  • Anything that has erratic characteristics. 

systematic

adj
  • Methodical, regular and orderly. 

  • Of or relating to taxonomic classification. 

  • Of, relating to, or being a system. 

  • Of, relating to, or in accordance with generally recognized conventions for the naming of chemicals. 

  • Treating an object as a system or coherent whole. 

  • Carried out according to a planned, ordered procedure. 

adv
  • systematically 

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