complexity vs morass

complexity

noun
  • That which is and renders complex; intricacy; complication. 

  • The state of being complex; intricacy; entanglement. 

morass

noun
  • Anything that entraps or makes progress difficult. 

  • A tract of soft, wet ground; a marsh; a fen. 

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