downshift vs throttle

downshift

noun
  • A shift of a transmission into a lower gear. 

  • A change in career or lifestyle to one which is not as well paid but less stressful and more personally rewarding. 

  • A change of direction or a movement downwards. 

  • A reduction in quality or quantity. 

verb
  • To reduce (something) in quality or quantity (as effect, scope, speed, etc.) 

  • To shift a transmission into a lower gear. 

  • To shift (a car or bicycle) into a lower gear. 

  • To function at a lower rate; to slacken. 

  • To change (one's career or lifestyle) to one which is not as well paid but less stressful and more personally rewarding. 

  • To change one's career or lifestyle to one which is not as well paid but less stressful and more personally rewarding. 

throttle

noun
  • The lever or pedal that controls this valve. 

  • A valve that regulates the supply of fuel-air mixture to an internal combustion engine and thus controls its speed; a similar valve that controls the air supply to an engine. 

verb
  • To utter with breaks and interruption, in the manner of a person half suffocated. 

  • To have the throat obstructed so as to be in danger of suffocation; to choke; to suffocate. 

  • To control or adjust the speed of (an engine). 

  • To breathe hard, as when nearly suffocated. 

  • To cut back on the speed of (an engine, person, organization, network connection, etc.). 

  • To strangle or choke someone. 

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