describe vs unfold

describe

verb
  • To represent by drawing; to draw a plan of; to delineate; to trace or mark out. 

  • To give rise to a geometrical structure. 

  • To represent in words. 

  • To introduce a new taxon to science by explaining its characteristics and particularly how it differs from other taxa. 

unfold

verb
  • To open (anything covered or closed); to lay open to view or contemplation; to bring out in all the details, or by successive development. 

  • To undo a folding. 

  • To release from a fold or pen. 

  • To turn out; to happen; to develop. 

  • To reveal. 

noun
  • In functional programming, a kind of higher-order function that is the opposite of a fold. 

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