dyed-in-the-wool vs occasional

dyed-in-the-wool

adj
  • Having the fibres dyed before they are formed into cloth. 

  • Firmly established in one's beliefs or habits; having a specified characteristic, identity, etc. deeply ingrained in one's nature. 

occasional

How often have the words dyed-in-the-wool and occasional occurred in a corpus of books? (source: Google Ngram Viewer )