single-hearted vs submissive

single-hearted

adj

  • Devoted; unambivalent and dedicated. 

  • Having an honest heart; straightforward, free from duplicity. 

submissive

adj

  • Meekly obedient or passive. 

noun

  • One who submits. 

  • One who submits to a dominant partner in BDSM practices. 

How often have the words single-hearted and submissive occurred in a corpus of books? (source: Google Ngram Viewer )