academy vs blackboard

academy

noun
  • A school or place of training in which some special art is taught. 

  • A society of learned people united for the advancement of the arts and sciences, and literature, or some particular art or science. 

  • Plato's philosophical system based on skepticism; Plato's followers. 

  • The garden where Plato taught. 

  • A school directly funded by central government, independent of local control. 

  • A body of established opinion in a particular field, regarded as authoritative. 

  • Academia. 

  • An institution for the study of higher learning; a college or a university; typically a private school. 

blackboard

noun
  • A large flat surface, finished with black slate or a similar material, that can be written upon with chalk and subsequently erased; a chalkboard. 

verb
  • To use a blackboard to assist in an informal discussion. 

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