oath vs retraction

oath

noun
  • A light, irreverent or insulting appeal to a deity or other entity. 

  • A curse, a curse word. 

  • A solemn pledge or promise that invokes a deity, a ruler, or another entity (not necessarily present) to attest the truth of a statement or sincerity of one's desire to fulfill a contract or promise. 

  • A statement or promise which is strengthened (affirmed) by such a pledge. 

retraction

noun
  • A continuous function from a topological space onto a subspace which is the identity on that subspace. 

  • An act or instance of retracting. 

  • A statement printed or broadcast in a public forum which effects the withdrawal of an earlier assertion, and which concedes that the earlier assertion was in error. 

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