absence vs apheresis

absence

noun
  • Inattention to things present; abstraction (of mind). 

  • A state of being away or withdrawn from a place or from companionship 

  • The period of someone being away. 

  • Temporary loss or disruption of consciousness, with sudden onset and recovery, and common in epilepsy. 

  • Lack; deficiency; nonexistence. 

  • Lack of contact between blades. 

  • Failure to be present where one is expected, wanted, or needed; nonattendance; deficiency. 

apheresis

noun
  • Elision, suppression, or complete loss of a letter or sound (syllable) from the beginning of a word, such as the development of special from especial; procope. 

  • The removal of blood from a patient, and the removal of certain components (such as platelets) from that blood, followed by the transfusion of the filtered blood back to the donor (patient). 

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