conjoin vs couple

conjoin

verb
  • To join together; to unite; to combine. 

  • To combine two sets, conditions, or expressions by a logical AND; to intersect. 

  • To marry. 

  • To unite, to join, to league. 

  • To join as coordinate elements, often with a coordinating conjunction, such as coordinate clauses. 

noun
  • A reassembled bone, stone or ceramic artifact. 

  • One of the words or phrases that are coordinated by a conjunction. 

couple

verb
  • To join (two things) together, or (one thing) to (another). 

  • To cause (two animals) to copulate, to bring (two animals) together for mating. 

  • To join in sexual intercourse; to copulate. 

noun
  • A small number. 

  • That which joins or links two things together; a bond or tie; a coupler. 

  • A couple-close. 

  • Two partners in a romantic or sexual relationship. 

  • One of the pairs of plates of two metals which compose a voltaic battery, called a voltaic couple or galvanic couple. 

  • Two of the same kind connected or considered together. 

  • A turning effect created by forces that sum to zero in magnitude but produce a non-zero external torque. 

det
  • Two or a few, a small number of. 

adj
  • Two or (a) small number of. 

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