hardener

American  

[hahr-dn-er] / ˈhɑr dn ər /

noun

1. a person or thing that hardens.

2. a substance mixed with paint or other protective covering to make the finish harder or more durable.

3. Photography. a chemical used to raise the melting point of an emulsion.

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ˈhardener British  

/ ˈhɑːdənə /

noun

1. a person or thing that hardens

2. a substance added to paint or varnish to increase durability

3. an ingredient of certain adhesives and synthetic resins that accelerates or promotes setting

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Etymology

Origin of hardener

First recorded in 1605–15; harden + -er ¹

Example Sentences

Research specialist Alex Baer painted the greenhouse’s exterior with several coats of whitewash mixed with a hardener to block the sun’s rays and help the coating withstand winter rainstorms.

From Los Angeles Times • May 31, 2023

You’d have to mix its two thick components — a polyamide hardener and an epoxy resin — and then carefully try to get it into the crack without making a mess.

From Seattle Times • Aug. 10, 2021

This week’s exhibition will also feature I’m Just a Little Tired – a visceral umbilical cord noose made from wool, textile hardener and silicone.

From The Guardian • Jul. 25, 2019

He treated these by saturating them with his own special blend of hardener.

From The New Yorker • Mar. 29, 2019

She was a harmful woman, a destroyer of young tempers, a hardener of young hearts.

From Stage Confidences by Morris, Clara