clustering vs concern

clustering

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

  • 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. 

adj
  • Forming a cluster. 

concern

noun
  • That which affects one’s welfare or happiness. A matter of interest to someone. 

  • The placement of interest or worry on a subject. 

  • The expression of solicitude, anxiety, or compassion toward a thing or person. 

  • A worry; a sense that something may be wrong; an identification of a possible problem. 

  • A business, firm or enterprise; a company. 

  • Any set of information that affects the code of a computer program. 

verb
  • To engage by feeling or sentiment; to interest. 

  • To relate or belong to; to have reference to or connection with; to affect the interest of; to be of importance to. 

  • To make somebody worried. 

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