common vs erratic

common

adj
  • Occurring or happening regularly or frequently; usual. 

  • Mutual; shared by more than one. 

  • Found in large numbers or in a large quantity; usual. 

  • Of or pertaining to common nouns as opposed to proper nouns. 

  • Simple, ordinary or vulgar. 

  • Of, pertaining or belonging to the common gender. 

  • Vernacular, referring to the name of a kind of plant or animal, i.e., common name vs. scientific name. 

noun
  • The right of taking a profit in the land of another, in common either with the owner or with other persons; so called from the community of interest which arises between the claimant of the right and the owner of the soil, or between the claimants and other commoners entitled to the same right. 

  • A tract of land in common ownership; common land. 

  • Mutual good, shared by more than one. 

  • The people; the community. 

erratic

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

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

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

  • Anything that has erratic characteristics. 

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