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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hardener 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

Mix the resin and hardener and press the mixture into the screw holes with a putty knife.

From Washington Post • Apr. 14, 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

The hardener is then able to become accustomed to the characteristics of that particular material, and after determining the most suitable treatment for it no further experimenting beyond the usual check-test pieces is necessary.

From The Working of Steel Annealing, Heat Treating and Hardening of Carbon and Alloy Steel by Colvin, Fred H. (Fred Herbert)