overswell vs spate

overswell

noun
  • An excessive or sudden increase or flood (of something). 

verb
  • To cause (something) to be too swollen or large; to become too swollen or large. 

  • To swell or rise above (something, especially the rim of a container, the sides of something hollow, etc.). 

spate

noun
  • A sudden rush or increase. 

  • A river flood; an overflow or inundation. 

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