absent vs unavailable

absent

adj
  • Not existing; lacking. 

  • Being away from a place; withdrawn from a place; not present; missing. 

  • Inattentive to what is passing; absent-minded; preoccupied. 

noun
  • Something absent, especially absent people collectively; those who were or are not there. 

verb
  • To keep (oneself) away. 

  • Leave. 

prep
  • In the absence of; without; except. 

unavailable

adj
  • Not available. 

noun
  • A communist who operated underground and was therefore not available for a political leadership position. 

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