spiny vs thorny

spiny

adj
  • Covered in spines or thorns 

  • Like a spine in shape; slender. 

  • Troublesome; difficult or vexing 

thorny

adj
  • Having thorns or spines 

  • Troublesome or vexatious 

  • Aloof and irritable 

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