menarche vs wane

menarche

noun
  • The onset of menstruation; a girl's first period. 

wane

noun
  • The end of a period. 

  • A gradual diminution in power, value, intensity etc. 

  • The lunar phase during which the sun seems to illuminate less of the moon as its sunlit area becomes progressively smaller as visible from Earth. 

  • A child. 

  • A rounded corner caused by lack of wood, often showing bark. 

  • ]] 

verb
  • To progressively lose its splendor, value, ardor, power, intensity etc.; to decline. 

  • Said of light that dims or diminishes in strength. 

  • Said of a time period that comes to an end. 

  • Said of the Moon as it passes through the phases of its monthly cycle where its surface is less and less visible. 

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