pain-free vs painful

pain-free

adj
  • without pain, free of pain. 

painful

adj
  • Afflicted or suffering with pain (of a body part or, formerly, of a person). 

  • Very bad, poor. 

  • Causing pain or distress, either physical or mental. 

  • Requiring effort or labor; difficult, laborious. 

How often have the words pain-free and painful occurred in a corpus of books? (source: Google Ngram Viewer )