pullulate vs trickle

pullulate

verb
  • To multiply rapidly. 

  • To teem; to be filled (with). 

  • To germinate. 

trickle

verb
  • To move or roll slowly. 

  • to flow in a very thin stream or drop continuously. 

  • to pour a liquid in a very thin stream, or so that drops fall continuously. 

noun
  • A very thin river. 

  • A very thin flow; the act of trickling. 

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