rill vs spate

rill

noun
  • A very small brook; a streamlet; a creek, rivulet. 

verb
  • To trickle, pour, or run like a small stream. 

spate

noun
  • A river flood; an overflow or inundation. 

  • A sudden rush or increase. 

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