copula vs harness

copula

noun
  • A device that connects two or more keyboards of an organ. 

  • A word, usually a verb, used to link the subject of a sentence with a predicate (usually a subject complement or an adverbial), that unites or associates the subject with the predicate. 

  • A function that represents the association between two or more variables, independent of the individual marginal distributions of the variables. 

  • The act of copulation; mating. 

harness

noun
  • A collection of wires or cables bundled and routed according to their function. 

  • A restraint or support, especially one consisting of a loop or network of rope or straps. 

  • The part of a loom comprising the heddles, with their means of support and motion, by which the threads of the warp are alternately raised and depressed for the passage of the shuttle. 

  • Equipment for any kind of labour. 

verb
  • To equip with armour. 

  • To place a harness on something; to tie up or restrain. 

  • To capture, control or put to use. 

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