exchange of contracts vs interchange

exchange of contracts

noun
  • The act of exchanging contracts. 

  • The point or stage at which a conveyancing contract comes into existence between negotiating parties for the carrying out of a disposition of an estate in land; usually requiring the payment of a deposit. 

interchange

noun
  • An act of interchanging. 

  • A connection between two or more lines, services or modes of transport; a station at which such a connection can be made. 

  • A highway junction in which traffic may change from one road to another without crossing a stream of traffic. 

verb
  • to swap or change places 

  • to alternate; to intermingle or vary 

  • to mutually give and receive (something); to exchange 

  • To act as or carry out an interchange (noun, senses 2, 3). 

  • to switch (each of two things) 

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