convolution vs zig

convolution

noun
  • A twist or fold. 

  • One 360° turn in a spring or similar helix. 

  • A mathematical operation on two functions that produces a third that expresses how the shape of one is modified by the other; the integral of the product of the two functions after one is reflected about the y-axis and shifted along the x-axis. 

  • The shape of something rotating; a vortex. 

  • Any of the folds on the surface of the brain. 

  • The state or condition of being convoluted. 

  • A function which maps a tuple of sequences into a sequence of tuples. 

zig

noun
  • A sudden or sharp turn or change of direction. 

verb
  • To make such a turn. 

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