slither vs thresh

slither

verb
  • To slide 

  • To move about smoothly and from side to side. 

noun
  • A limestone rubble. 

  • A sliver. 

thresh

verb
  • To violently toss the limbs about. 

  • To beat soundly, usually with some tool such as a stick or whip; to drub. 

  • To separate the grain from the straw or husks (chaff) by mechanical beating, with a flail or machinery. 

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