immensity vs infinity

immensity

noun
  • The state or characteristic of being immense. 

  • An immense object. 

infinity

noun
  • endlessness, unlimitedness, absence of a beginning, end or limits to size. 

  • A number that has an infinite numerical value that cannot be counted. 

  • The symbol ∞. 

  • A number which is very large compared to some characteristic number. For example, in optics, an object which is much further away than the focal length of a lens is said to be "at infinity", as the distance of the image from the lens varies very little as the distance increases further. 

  • An idealised point which is said to be approached by sequences of values whose magnitudes increase without bound. 

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