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

The research paid special attention to people with high blood pressure and also examined a subgroup of adults considered safe candidates for salt substitutes.

From Science Daily • Mar. 31, 2026

The subgroup of panel members that recommended the change also said it understood that “the safety concern may be more theoretical than real.”

From The Wall Street Journal • Dec. 6, 2025

A lieutenant tattooed with that image previously testified that it is associated with the Gladiators deputy subgroup, of which Fernandez has denied being a member.

From Los Angeles Times • Jun. 6, 2025

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

As a subgroup, relos are economically homogenous, with midcareer incomes starting at $100,000 a year.

From "Class Matters" by The New York Times