approval vs rumble

approval

noun
  • Something mailed by a seller to a collector to match their stated interests; the collector can approve of or return the item. 

  • An expression granting permission; an indication of agreement with a proposal; an acknowledgement that a person, thing, or event meets requirements. 

  • An expression of favorable acceptance and encouragement; a compliment that also condones. 

rumble

verb
  • To move while making a rumbling noise. 

  • To make a low, heavy, continuous sound. 

  • To fight; to brawl. 

  • to provide haptic feedback by vibrating. 

  • To cause to pass through a rumble, or polishing machine. 

  • To discover deceitful or underhanded behaviour. 

noun
  • A street fight or brawl. 

  • A rotating cask or box in which small articles are smoothed or polished by friction against each other. 

  • A low, heavy, continuous sound, such as that of thunder or a hungry stomach. 

intj
  • An onomatopoeia describing a rumbling noise 

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