breakthrough vs complication

breakthrough

adj
  • Involving the contraction of a disease by a person with a decreased susceptibility, such as a person who has been vaccinated to help prevent that disease. 

  • Characterized by major progress or overcoming some obstacle. 

  • The emergence or one or more symptoms of a condition despite medication or other medical treatment. 

noun
  • The penetration of the opposition's defence. 

  • An advance through and past enemy lines. 

  • Any major progress; such as a great innovation or discovery that overcomes a significant obstacle. 

  • The penetration of a separating wall or the remaining distance to an adjacent hollow (a crosscut in mining) or between two parts of a tunnel build from both ends; knockthrough. 

complication

noun
  • 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. 

  • The act or process of complicating. 

  • 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. 

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