class action

noun

: a legal action undertaken by one or more plaintiffs on behalf of themselves and all other persons having an identical interest in the alleged wrong

Examples of class action in a Sentence

Recent Examples on the Web

Last month, Froble certified the case as a class action involving 570 families who had received religious exemptions in other parts of the state. —Landon Mion, FOXNews.com, 27 Nov. 2025

What To Know The decision stems from a class action brought by four noncitizens arrested during large-scale immigration raids in Southern California in June 2025. —Robert Alexander, MSNBC Newsweek, 26 Nov. 2025

The group’s website is focused on Mangione along with stories of people who say they or a family member were injured or died because of health-care denials, including one man seeking to file a class action lawsuit over the loss of his leg. —Lorena O'Neil, Rolling Stone, 24 Nov. 2025

At least four families have sued infant formula maker ByHeart saying their babies contracted botulism from contaminated formula, as the company faces ongoing scrutiny from federal investigators and a separate class action lawsuit filed last week. —Aria Bendix, NBC news, 22 Nov. 2025

Word History

First Known Use

1909, in the meaning defined above

Rhymes for class action

• abstraction
• attraction
• compaction
• contraction
• detraction
• diffraction
• distraction
• exaction
• extraction
• impaction
• inaction
• infraction

Legal Definition

class action

noun

: an action in which a representative plaintiff sues or a representative defendant is sued on behalf of a class of plaintiffs or defendants who have the same interests in the litigation as their representative and whose rights or liabilities can be more efficiently determined as a group than in a series of individual suits

called also class action suit, class suit

see also certification compare consolidate, joinder, test case at case

Note: Rule 23 of the Federal Rules of Civil Procedure sets out the prerequisites for having an action certified as a class action in federal court. Section (a) permits a class action if “(1) the class is so numerous that joinder of all members is impracticable, (2) there are questions of law or fact common to the class, (3) the claims or defenses of the representative parties are typical of the claims or defenses of the class, and (4) the representative parties will fairly and adequately protect the interests of the class.” If the action satisfies these requirements, it must then fit into one of three categories: (1) where individual litigation would have varying results requiring the opposing party to act inconsistently toward the class members or would affect the interests of class members who are not parties to the individual action; (2) where the opposing party has acted or refused to act on grounds that are applicable to the class members as a whole and therefore injunctive or declaratory relief with respect to the class members as a whole is appropriate; or, (3) where the questions of law or fact common to the class members outweigh questions that apply to only particular individuals so that a class action is the best method to determine respective rights and liabilities. Using these guidelines, the judge will decide if an action should be certified as a class action.