expedition vs retardation

expedition

verb
  • To take part in a trip or expedition; to travel. 

noun
  • An important or long journey, for example a march or a voyage 

  • The group of people making such excursion. 

  • A military journey; an enterprise against some enemy or into enemy territory. 

  • A trip, especially a long one, made by a person or a group of people for a specific purpose 

  • The process or activities of performing expediter tasks. 

retardation

noun
  • The distance by which one wave is behind another. 

  • The extent to which anything is retarded; the result of any retarding or delay; mental, social, or physical slowness. 

  • Deceleration; reduction in the magnitude of velocity. 

  • That which retards; an obstacle; an obstruction. 

  • Extreme stupidity. 

  • A decrease in the speed of telegraph signalling. 

  • A suspension which resolves upwards. 

  • The act of diminishing the rate of speed. 

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