averment vs oath

averment

noun
  • A positive statement of facts; an allegation; an offer to justify or prove what is alleged. 

  • The act of averring, or that which is averred; positive assertion. 

  • verification; establishment by evidence. 

oath

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

  • 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. 

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