flechette vs ricochet

flechette

noun
  • A small sharp antipersonnel projectile, used as shrapnel, fired from a shotgun, or scattered from an aircraft. 

ricochet

noun
  • A method of firing a projectile so that it skips along a surface. 

  • An instance of ricocheting; a glancing rebound. 

verb
  • To operate upon by ricochet firing. 

  • To rebound off something wildly in a seemingly random direction. 

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