ebullience vs flatness

ebullience

noun
  • A boiling or bubbling up; an ebullition. 

  • The quality of enthusiastic or lively expression of feelings and thoughts. 

flatness

noun
  • slim-tailedness or platykurticity 

  • The state of being bland : dullness 

  • Lack of bouquet and freshness of a wine, through too much aeration or infection with film yeasts 

  • The state of being flat 

  • The state of being two-dimensional; planar : planarity 

  • Mattness, the quality of a painted surface which scatters or absorbs the light falling on it, so as to be substantially free from gloss or sheen 

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