a priori vs notional

a priori

adj
  • Presumed without analysis. 

  • Self-evident, intuitively obvious. 

  • Based on hypothesis and theory rather than experiment or empirical evidence. 

  • Developed entirely from scratch, without deriving it from existing languages. 

adv
  • In a way based on theoretical deduction rather than empirical observation. 

notional

adj
  • Speculative, theoretical, not the result of research. 

  • Having descriptive value as opposed to a syntactic category. 

  • Used to indicate an estimate or a reference amount 

  • Full of ideas or imaginings. 

  • Of, containing, or being a notion; mental or imaginary. 

noun
  • A fake company used as a front in espionage. 

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