erratic vs ponderous

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. 

ponderous

adj
  • Characterized by or associated with pondering. 

  • Heavy, massive, weighty. 

  • Clumsy, unwieldy, or slow, especially due to weight. 

  • Serious, onerous, oppressive. 

  • Dull, boring, tedious; long-winded in expression. 

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