join vs pertain

join

verb
  • To enter into association or alliance, to unite in a common purpose. 

  • To unite in marriage. 

  • To produce an intersection of data in two or more database tables. 

  • To come into the company of. 

  • To come together; to meet. 

  • To accept, or engage in, as a contest. 

  • To become a member of. 

  • To connect or combine into one; to put together. 

noun
  • An intersection of data in two or more database tables. 

  • The act of joining something, such as a network. 

  • The lowest upper bound, an operation between pairs of elements in a lattice, denoted by the symbol ∨. 

  • An intersection of piping or wiring; an interconnect. 

pertain

verb
  • To belong to or be a part of; be an adjunct, attribute, or accessory of. 

  • To apply; to be or remain in place; to continue to be applicable. 

  • To relate, to refer, be relevant to. 

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