subgroup

[suhb-groop] /ˈsʌbˌgrup/
noun
1.
a subordinate group; a division of a group.
2.
Chemistry. a division of a group in the periodic table.
3.
Mathematics. a subset of a group that is closed under the group operation and in which every element has an inverse in the subset.
Origin
1835-45; sub- + group
Examples from the web for subgroup
  • The subgroup of people with mild cognitive impairment also improved.
  • Meanwhile, neither subgroup of rats on low-fat chow gained any significant excess weight.
  • It is a subgroup of the isometry group of the space concerned.
British Dictionary definitions for subgroup

subgroup

/ˈsʌbˌɡruːp/
noun
1.
a distinct and often subordinate division of a group
2.
a mathematical group whose members are members of another group, both groups being subject to the same rule of combination