clustering vs collocation

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. 

collocation

noun
  • Such a specific grouping. 

  • A method of finding an approximate solution of an ordinary differential equation L[y]=0 by determining coefficients in an expansion y(x)=y_0(x)+∑ₗ₌₀^q𝛼ₗy_l(x) so as to make L[y] vanish at prescribed points; the expansion with the coefficients thus found is the sought approximation. 

  • The grouping or juxtaposition of things, especially words or sounds. 

  • A sequence of words or terms that co-occur more often than would be expected by chance (i.e., the statistically significant placement of particular words in a language), often representing an established name for, or idiomatic way of conveying, a particular semantic concept. 

  • A service allowing multiple customers to locate network, server, and storage gear and connect them to a variety of telecommunications and network service providers, at a minimum of cost and complexity. 

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