ambiguity vs equivocation

ambiguity

noun
  • words or statements that are open to more than one interpretation, explanation or meaning, especially if that meaning cannot be determined from its context. 

  • The state of being ambiguous. 

equivocation

noun
  • A logical fallacy resulting from the use of multiple meanings of a single expression. 

  • The use of expressions susceptible of a double signification, possibly intentionally and with the aim of misleading. 

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