achromasia vs lividity

achromasia

noun
  • Absence of normal skin pigmentation (from bruising, stress or disease); pallor or achromia. 

  • The inability of a cell or tissue to be stained. 

lividity

noun
  • A livid area of skin, such as a bruise, or as is often found on cadavers. 

  • Livor mortis, suggillation. 

  • The state or quality of being livid. 

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