nonstimulating vs wishy-washy

nonstimulating

adj
  • Not stimulating. 

wishy-washy

adj
  • Thin or watery. 

  • Wavering; lacking in commitment, certainty, or support; namby-pamby. 

How often have the words nonstimulating and wishy-washy occurred in a corpus of books? (source: Google Ngram Viewer )