headstrong vs immovable

headstrong

adj
  • Determined to do as one pleases, and not as others want. 

immovable

adj
  • steadfast in purpose or intention; unalterable, unyielding 

  • not capable of being affected or moved in feeling; impassive 

  • not liable to be removed; permanent in place or tenure; fixed 

  • incapable of being physically moved; fixed 

noun
  • that which can not be moved; something which is immovable 

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