subgroup

American  

[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.

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subgroup British  

/ 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

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Etymology

Origin of subgroup

First recorded in 1835–45; sub- + group

Example Sentences

More specifically, it belonged to a subgroup called Euhelopodidae, which is known only from Asia.

From Science Daily • May 15, 2026

Goldman, however, is not on the list of primary dealers, or a subgroup of dealers that are allowed to bid on up to 25% of auctioned amounts.

From The Wall Street Journal • May 14, 2026

"There was recognition that there is a very small subgroup of children whose gender incongruence persists long-term and who may require ongoing support and possible medical interventions," the review said.

From BBC • Feb. 10, 2026

But it’s also worth remembering that the further you drill into subgroup data of any individual poll, the higher the margin of error and the less confidence we can have in the results.

From Slate • May 22, 2025

Next come crops whose names are consistent only among the languages falling within a small subgroup of those southern Nigerian languages.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond