forenoon vs noontime

forenoon

noun
  • Synonym of morning: the part of the day between sunrise and noon. 

noontime

noun
  • Noon. 

  • Approximately noon. 

  • The time at which something peaks in some way (e.g., in vitality, in influence, in reknown) (by analogy with the waxing of the sun each day). 

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