irregular vs nonstop

irregular

adj
  • without symmetry, regularity, or uniformity 

  • rough 

  • not regular; having sides that are not equal or angles that are not equal 

  • whose faces are not all regular polygons (or are not equally inclined to each other) 

  • nonstandard; not conforming to rules or expectations 

  • not following the regular or expected patterns of inflection in a given language 

noun
  • A soldier who is not a member of an official military force and who may not use regular army tactics. 

  • One who does not regularly attend a venue. 

nonstop

adj
  • Without stopping; without interruption or break. 

  • Describing a point mutation within a stop codon that causes the continued translation of an mRNA strand. 

adv
  • Without stopping; without interruption or break 

noun
  • A linguistic sound that is not a stop; a continuant. 

  • A convenience store in parts of Europe, open 24 hours a day. 

  • A nonstop journey, especially a nonstop flight. 

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