herd vs separation

herd

noun
  • A crowd, a mass of people or things; a rabble. 

  • A number of domestic animals assembled together under the watch or ownership of a keeper. 

  • Any collection of animals gathered or travelling in a company. 

verb
  • To manage, care for or guard a herd 

  • To act as a herdsman or a shepherd. 

  • To unite or associate in a herd 

  • To move or drive a herd. 

  • To associate; to ally oneself with, or place oneself among, a group or company. 

  • To unite or associate in a herd; to feed or run together, or in company. 

  • To form or put into a herd. 

separation

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

  • 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 place at which a division occurs. 

  • 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 herd and separation occurred in a corpus of books? (source: Google Ngram Viewer )