clustering vs compression

clustering

adj
  • Forming a cluster. 

noun
  • The undesirable contiguous grouping of elements in a hash table. 

  • A grouping of a number of similar things. 

  • A prewriting technique consisting of writing ideas down on a sheet of paper around a central idea within a circle, with the related ideas radially joined to the circle using rays. 

  • The grouping of a population based on ethnicity, economics or religion. 

compression

noun
  • The cycle of an internal combustion engine during which the fuel and air mixture is compressed. 

  • An increase in density; the act of compressing, or the state of being compressed; compaction. 

  • The electronic process by which any sound's gain is automatically controlled. 

  • The deviation of a heavenly body from a spherical form. 

  • The process by which data is compressed. 

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