1. a person or party who intervenes in a legal proceeding to which they were not originally a party
Usage: legal
2. a person who intervenes in a situation or dispute

Examples

• The environmental group filed a motion to become an intervenor in the pipeline lawsuit.
• The court allowed the union to join as an intervenor in the contract dispute.
• Several intervenors presented arguments during the regulatory hearing.
• The insurance company sought intervenor status in the personal injury case.
• As an intervenor, she helped resolve the neighborhood conflict.
• The federal agency acted as an intervenor in the state’s water rights case.