1. a substance or product that makes something brighter or whiter
2. something that improves or enhances a situation
Usage: figurative

Examples

• She added fabric brightener to the washing machine to keep her white clothes looking new.
• The optical brightener in the detergent made the shirts appear whiter under fluorescent lights.
• A smile can be a real brightener on a gloomy day.
• The new paint job was a brightener for the old kitchen.
• Many laundry products contain brighteners to enhance the appearance of fabrics.
• His cheerful attitude served as a brightener during the difficult meeting.