glade vs polder

glade

noun
  • An open space in the ice on a river or lake. 

  • An everglade. 

  • An open passage through a wood; a grassy open or cleared space in a forest. 

  • A bright surface of ice or snow. 

polder

noun
  • An area of ground reclaimed from a sea or lake by means of dikes. 

verb
  • To reclaim an area of ground from a sea or lake by means of dikes. 

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