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

Because the case was filed as a class action lawsuit, if a judge sides with the plaintiffs, that decision will apply not just to the 17 scientist plaintiffs, but to any researcher whose work has been affected by the term searches. — Anil Oza, STAT, 17 Sep. 2026

Mass tort lawyers are also offering up help on social media to people who live near data centers and filing class action lawsuits against operators. — Nathaniel Meyersohn, CNN Money, 11 Sep. 2026

California residents Nicholas Farrell and Jeff Ganan separately filed class actions against LinkedIn in April, seeking to represent themselves and other LinkedIn users. — Jon Brodkin, ArsTechnica, 10 Sep. 2026

He was also recognized in The Best Lawyers in America for 2024 and 2025 for his work in mass tort and class action litigation. — Matt Emma, USA Today, 9 Sep. 2026

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.