long-term vs permanent

long-term

adj
  • Extending over a relatively long time period. 

  • Becoming evident after a relatively long time period. 

permanent

adj
  • Lasting for an indefinitely long time. 

  • Without end, eternal. 

noun
  • A card whose effects persist beyond the turn on which it is played. 

  • A chemical hair treatment imparting or removing curliness, whose effects typically last for a period of weeks; a perm. 

  • Given an n⨯n matrix a_ij,, the sum over all permutations 𝜋, of ∏ᵢ₌₁ⁿa_i𝜋(i). 

How often have the words long-term and permanent occurred in a corpus of books? (source: Google Ngram Viewer )