clustering vs genus

clustering

noun
  • A grouping of a number of similar things. 

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

  • 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. 

adj
  • Forming a cluster. 

genus

noun
  • A group with common attributes. 

  • A taxon at this rank. 

  • A natural number representing any of several related measures of the complexity of a given manifold or graph. 

  • A category in the classification of organisms, ranking below family (Lat. familia) and above species. 

  • Within a definition, a broader category of the defined concept. 

  • A type of tuning or intonation, used within an Ancient Greek tetrachord. 

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