1. A woman who has the power to decide or settle a dispute; a female arbitrator.
Usage: formal; less common than the gender-neutral term 'arbitrator'
2. A woman who has supreme power or authority over something; a female arbiter.
Usage: formal; often used in literary or historical contexts

Examples

• The arbitress heard arguments from both parties before making her decision.
• She served as arbitress in the labor dispute between the union and management.
• The arbitress of fashion in the 1920s was known for her bold choices.
• An arbitress was appointed to resolve the contract disagreement.
• The arbitress wielded considerable influence over the outcome of the case.