hardening

American  

[hahr-dn-ing] / ˈhɑr dn ɪŋ /

noun

1. a material that hardens another, as an alloy added to iron to make steel.

2. the process of becoming hard or rigid.

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hardening British  

/ ˈhɑːdənɪŋ /

noun

1. the act or process of becoming or making hard

2. a substance added to another substance or material to make it harder

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Etymology

Origin of hardening

First recorded in 1620–30; harden + -ing ¹

Example Sentences

AI data centers, manufacturing, and grid hardening against severe weather are driving investments, with half for transmission system upgrades.

From The Wall Street Journal • Apr. 14, 2026

Iran is hardening defenses on Kharg Island, Ebrahim Azizi, the head of the parliament’s National Security Commission, told the legislature’s news agency this week.

From Barron's • Apr. 3, 2026

A 2018 server breach caused by a third-party data center vulnerability prompted NordVPN to accelerate its security hardening and audit schedule.

From Salon • Mar. 27, 2026

The metal shutters and advanced outdoor sprinkler system are the flashiest parts of Tavangarian’s home hardening project, and the efficacy of these adaptations is still up for debate.

From Los Angeles Times • Mar. 2, 2026

It had been hours, now, since all this began, the first twinge, then the rhythmic, hardening pain, and later, the buckling on of the mask.

From "Son" by Lois Lowry

Related Words

• crystallization