raving vs unstable

raving

adj
  • Talking wildly. 

  • Causing excitement or wild praise. 

noun
  • Wild, incoherent, or irrational talk. 

adv
  • Incoherently 

unstable

adj
  • Fickle. 

  • Readily decomposable. 

  • Not stable. 

  • Radioactive, especially with a short half-life. 

  • Unpredictable. 

  • Having a strong tendency to change. 

  • Fluctuating; not constant. 

verb
  • To release (an animal) from a stable. 

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