Definitions

1. noun

Something that makes or makes something appear brighter, whiter, or more radiant.

“The brightener in the new laundry detergent helped remove tough stains.”

2. noun

A substance, especially a chemical, that is added to a material, such as paint or plastics, to improve its color or appearance.

“The manufacturer added a brightener to the paint to make it more vibrant and appealing to consumers.”