degenerate vs turn back

degenerate

verb
  • To cause to lose good or desirable qualities. 

  • To lose good or desirable qualities. 

noun
  • One who is degenerate, who has fallen from previous stature. 

adj
  • Having lost good or desirable qualities. 

  • Having deteriorated, degraded or fallen from normal, coherent, balanced and desirable to undesirable and typically abnormal; an immoral or corrupt person. 

  • Having the same quantum energy level. 

  • Having multiple domain elements correspond to one element of the range. 

  • Having multiple different (linearly independent) eigenvectors. 

turn back

verb
  • To prevent or refuse to allow passage or progress. 

  • To cause to reverse direction and retrace one's steps. 

  • To return to a previous state of being. 

  • To reverse direction and retrace one's steps. 

  • To adjust to a previous setting. 

  • To fold something back; to fold down. 

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