complication vs opening

complication

noun
  • The act or process of complicating. 

  • A person who doesn't fit in with the main scheme of things; an interloper. 

  • The state of being complicated; intricate or confused relation of parts; complexity. 

  • A feature beyond basic time display in a timepiece. 

  • A disease or diseases, or adventitious circumstances or conditions, coexistent with and modifying a primary disease, but not necessarily connected with it. 

opening

noun
  • An act or instance of making or becoming open. 

  • The first few measures of a musical composition. 

  • The first performance of a show or play by a particular troupe. 

  • A gap permitting passage through. 

  • The initial period when a show at an art gallery or museum is first opened, especially the first evening. 

  • A vacant position, especially in an array. 

  • An unoccupied employment position. 

  • In mathematical morphology, the dilation of the erosion of a set. 

  • A time available in a schedule. 

  • An opportunity, as in a competitive activity. 

  • An act or instance of beginning. 

  • The first few moves in a game. 

adj
  • Pertaining to the start or beginning of a series of events. 

  • describing the first period of play, usually up to the fall of the first wicket; describing a batsman who opens the innings or a bowler who opens the attack 

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