dichotomy vs separation

dichotomy

noun
  • A separation or division into two; a distinction that results in such a division. 

  • The division of a genus into two species; a division into two subordinate parts. 

  • A phase of the moon when it appears half lit and half dark, as at the quadratures. 

  • Such a division involving apparently incompatible or opposite principles; a duality. 

  • The division of a class into two disjoint subclasses that are together comprehensive, as the division of man into white and not white. 

  • Division and subdivision; bifurcation, as of a stem of a plant or a vein of the body into two parts as it proceeds from its origin; often successive. 

separation

noun
  • The place at which a division occurs. 

  • Departure from active duty, while not necessarily leaving the service entirely. 

  • An agreement legalizing such an arrangement. 

  • An object that separates two spaces. 

  • The act of disuniting two or more things, or the condition of being separated. 

  • The act or condition of two or more people being separated from one another. 

  • An interval, gap or space that separates things or people. 

  • The act or condition of a married couple living in separate homes while remaining legally married. 

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