parallelism vs simultaneity

parallelism

noun
  • The state or condition of being parallel; agreement in direction, tendency, or character. 

  • A parallel position; the relation of parallels. 

  • The doctrine that matter and mind do not causally interact but that physiological events in the brain or body nonetheless occur simultaneously with matching events in the mind. 

  • Similarity of features between two species resulting from their having taken similar evolutionary paths following their initial divergence from a common ancestor. 

  • The use of parallel methods in hardware or software, so that several tasks can be performed at the same time. 

  • The state of being in agreement or similarity; resemblance, correspondence, analogy. 

  • In antitrust law, the practice of competitors of raising prices by roughly the same amount at roughly the same time, without engaging in a formal agreement to do so. 

  • The juxtaposition of two or more identical or equivalent syntactic constructions, especially those expressing the same sentiment with slight modifications, introduced for rhetorical effect. 

simultaneity

noun
  • The quality or state of being simultaneous; simultaneousness. 

  • More than one complete musical texture occurring at the same time. This first appeared in the music of Charles Ives, and is common in the music of Conlon Nancarrow, and others. 

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