irregular vs pretender

irregular

noun
  • One who does not regularly attend a venue. 

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

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 

pretender

noun
  • A person who professes beliefs and opinions that they do not hold. 

  • A claimant to a throne or the office of a ruler; orig. in a neutral sense, but now always applied to a claimant who is held to have no just title. 

  • One who puts forth a claim, or who aspires to or aims at something; a claimant, candidate, or aspirant; now, one who makes baseless pretensions. 

  • A claimant to an abolished or already occupied throne. 

  • One who pretends or lays claim to something; one who makes a profession, show, or assertion, esp. without adequate grounds, falsely, or with intent to deceive; a dissembler, deceiver, charlatan, hypocrite. 

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