Brightener

Part of speech: noun

Definitions

1. A substance added to make colors or surfaces appear more vivid or luminous
2. An agent that enhances the visual brightness of objects or materials
3. A chemical or additive used to increase the brightness or shine of items

Etymology: Brightener is about as transparent as English compounds get: the verb "brighten" with the agent suffix "-er" attached, so it names whatever brightens something. The verb itself has a longer ancestry. It traces back to the Germanic adjective behind Old English "beorht", meaning bright or shining, and it was formed in Middle English with the causative suffix "-en", meaning to make something into the quality named by the adjective. The noun is simply the verb's agent form, built on the same pattern as "baker" or "teacher". It is a plain English formation rather than a borrowing, so its interest lies in the sense it picks out: a substance that makes things whiter or more luminous, most familiar from laundry products and paper treatments.

Synonyms: whitener, enhancer