dashpot vs shock absorber

dashpot

noun
  • A mechanical damping device consisting of a piston that moves through a viscous fluid (usually oil); used, in conjunction with a spring, in shock absorbers. 

shock absorber

noun
  • A mechanical device designed to smooth out or damp any sudden shock impulse and dissipate kinetic energy; usually consists of a combination of a spring and a dashpot. 

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