nonplus vs ravel

nonplus

verb
  • To bewilder or perplex (someone); to confound, to flummox. 

noun
  • A state of bewilderment or perplexity. 

ravel

verb
  • To confuse or perplex (someone or something). 

  • To unwind (a reel of thread, a skein of yarn, etc.); to pull apart (cloth, a seam, etc.); to fray, to unpick, to unravel; also, to pull out (a string of yarn, a thread, etc.) from a piece of fabric, or a skein or reel. 

  • To entwine or tangle (something) confusedly; to entangle. 

  • To become entangled or snarled. 

  • Often followed by up: to form (something) out of discrete elements, like weaving fabric from threads; to knit. 

  • Often followed by out: of a reel of thread or skein of yarn; or a thread on a reel or a string of yarn in a skein, etc.: to become untwisted or unwound. 

  • Often followed by out: of clothing, fabric, etc.: to become unwoven; to fray, to unravel. 

  • In the APL programming language: to reshape (a variable) into a vector. 

noun
  • A thread which has unravelled from fabric, etc.; also, a situation of fabric, etc., coming apart; an unravelling. 

  • A tangled mess; an entanglement, a snarl, a tangle. 

  • A confusing, intricate, or perplexing situation; a complication. 

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