clockwork vs wristwatch

clockwork

noun
  • A mechanism powered by a coiled spring and regulated by some form of escapement; the power is transmitted through toothed gearwheels and used to drive a mechanical clock, toy, or other device. 

  • The action of behaving mechanically in the manner of a clock. 

adj
  • Very smooth and regular. 

  • Driven by clockwork. 

wristwatch

noun
  • A watch that is worn on a strap or band fastened around the wrist 

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