equivocation vs uncertainty

equivocation

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

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

uncertainty

noun
  • Something uncertain or ambiguous. 

  • Doubt; the condition of being uncertain or without conviction. 

  • A parameter that measures the dispersion of a range of measured values. 

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