clustered

Concise Oxford English Dictionary © 2008 Oxford University Press:
cluster/ˈklʌstə(r)/

▶noun

• 1 a group of similar things or people positioned or occurring closely together.

  ■ a natural subgroup of a population, used for statistical sampling or analysis.

• 2 Chemistry a group of atoms of the same element, typically a metal, bonded closely together in a molecule.

▶verb form a cluster.

■ Statistics (of data points) have similar numerical values.

– derivatives
clustered adjective.

– origin OE clyster; prob. rel. to clot.