complex vs old boy network

complex

noun
  • An assemblage of related things; a collection. 

  • A structure consisting of a central atom or molecule weakly connected to surrounding atoms or molecules, as for example coordination complexes in inorganic chemistry and protein complexes in biochemistry. 

  • A multimorphemic word, one with several parts, one with affixes. 

  • A problem. 

  • An abnormal mental condition caused by repressed emotions. 

  • A cluster of wildfires burning in the same vicinity. 

  • A group of closely related species, often distinguished only with difficulty by traditional morphological methods. 

  • An organized cluster of thunderstorms. 

  • A vehement, often excessive psychological dislike or fear of a particular thing. 

  • A complex number. 

  • A collection of buildings with a common purpose, such as a university or military base. 

  • A network of interconnected systems. 

verb
  • To complicate. 

  • To form a complex with another substance 

adj
  • A curve, polygon or other figure that crosses or intersects itself. 

  • Having the form a + bi, where a and b are real numbers and i is (by definition) the imaginary square root of −1. 

  • Made up of multiple parts; composite; not simple. 

  • Whose range is a subset of the complex numbers. 

  • Whose coefficients are complex numbers; defined over the field of complex numbers. 

  • Not simple, easy, or straightforward; complicated. 

old boy network

noun
  • A presumed unacknowledged system of association between childhood friends (especially those at school or university together), used for mutual assistance or favouritism. 

How often have the words complex and old boy network occurred in a corpus of books? (source: Google Ngram Viewer )