linkage vs merger

linkage

noun
  • The act or result of linking: the combination of multiple object files into one executable, library, or object file. 

  • A connection or relation between things or ideas. 

  • A United States foreign policy, during the 1970s détente in the Cold War, of persuading the Soviet Union to co-operate in restraining revolutions in the Third World in return for nuclear and economic concessions. 

  • A mechanical device that connects things. 

  • The property of genes of being inherited together. 

  • A set of definitely related languages for which no proto-language can be derived, typically a group of languages within a family that have formed a sprachbund. 

merger

noun
  • The act or process of merging two or more parts into a single unit. 

  • A type of sound change where two or more sounds merge into one. 

  • One that merges. 

  • The legal union of two or more corporations into a single entity, typically assets and liabilities being assumed by the buying party. 

  • An absorption of one or more estate(s) or contract(s) into one other, all being held by the same owner; of several counts of accusation into one judgement, etc. 

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