contrivance vs instrument

contrivance

noun
  • A (mechanical) device to perform a certain task. 

  • Something overly artful or artificial. 

  • A means, such as an elaborate plan or strategy, to accomplish a certain objective. 

instrument

noun
  • A tool, implement used for manipulation or measurement. 

  • A legal document, such as a contract, deed, trust, mortgage, power, indenture, or will. 

  • A device used to produce music. 

  • A means or agency for achieving an effect. 

  • A person used as a mere tool for achieving a goal. 

  • A measuring or displaying device. 

verb
  • To devise, conceive, cook up, plan. 

  • To perform upon an instrument; to prepare for an instrument. 

  • To apply measuring devices. 

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