harden

verb

hard·​en ˈhär-dᵊn How to pronounce harden (audio)
hardened; hardening ˈhärd-niŋ How to pronounce harden (audio)
ˈhär-dᵊn-iŋ

transitive verb

1
: to make hard or harder
2
: to confirm in disposition, feelings, or action
especially : to make callous
hardened his heart
3
a
: inure, toughen
harden troops
b
: to inure to unfavorable environmental conditions (such as cold)
often used with off
harden off seedlings before transplanting
4
: to protect from blast, heat, or radiation (as by a thick barrier or placement underground)

intransitive verb

1
: to become hard or harder
2
a
: to become firm, stable, or settled
b
: to assume an appearance of harshness or severity
her face hardened at the thought
3
: to become gradually acclimatized to unfavorable conditions
often used with off
plants hardened off before the first frost

Examples of harden in a Sentence

The presence of certain substances in the blood can cause the arteries to harden. These additives are designed to harden the steel. substances that can harden the arteries The news has hardened opposition to the government. He had been hardened by his years of military service.
Recent Examples on the Web The companies also are spending heavily to harden their equipment, replacing old wooden power poles, covering some power lines with a protective sheath while burying others underground. David R. Baker, Fortune, 7 Mar. 2024 But attitudes toward the law — at least in certain circles — have been hardening recently. Meagan Flynn, Washington Post, 7 Mar. 2024 And for now, the leak and Moscow’s response may well harden Mr. Scholz’s view. Ned Temko, The Christian Science Monitor, 7 Mar. 2024 The hurt and anger between Prince William and Prince Harry, in particular, has now hardened into something colder and more immovable, said Scobie: indifference. Stephanie Petit, Peoplemag, 16 Feb. 2024 Nicotine may also harden the walls of arteries in the heart, contributing to heart disease and attacks. Dani Blum, San Diego Union-Tribune, 7 Feb. 2024 Within the Ottoman empire, divisions between the two communities also hardened as a result of the Tanzimat, a series of 19th-century reforms, which unintentionally spawned new modes of allegiance and proto-nationalisms among different minority groups within the empire. TIME, 1 Feb. 2024 Finland, which shares an 800-mile border with Russia, spent decades hardening its defenses following the 1939-1940 Winter War with its eastern neighbor. Emily Rauhala, Washington Post, 24 Feb. 2024 Steps to harden America’s grid against EMPs have long been underway but are progressing too slowly. Ariel Cohen, Forbes, 22 Feb. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'harden.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

13th century, in the meaning defined at transitive sense 1

Time Traveler
The first known use of harden was in the 13th century

Dictionary Entries Near harden

Cite this Entry

“Harden.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/harden. Accessed 19 Mar. 2024.

Kids Definition

harden

verb
hard·​en ˈhärd-ᵊn How to pronounce harden (audio)
hardened; hardening ˈhärd-niŋ How to pronounce harden (audio)
-ᵊn-iŋ
1
: to make or become hard or harder
2
: to make unfeeling or unsympathetic
hardened his heart
3
: to make or become hardy or strong
muscles hardened by exercise
4
: to protect from blast, heat, or radiation (as by a thick barrier or by placing underground)
hardened missile sites
5
a
: to become firm, stable, or settled
b
: to express harshness
hardener
ˈhärd-nər
-ᵊn-ər
noun

Biographical Definition

Harden 1 of 2

biographical name (1)

Har·​den ˈhär-dᵊn How to pronounce Harden (audio)
Sir Arthur 1865–1940 English chemist

Harden

2 of 2

biographical name (2)

Maximilian 1861–1927 originally Felix Ernst Witkowski German writer

More from Merriam-Webster on harden

Last Updated: - Updated example sentences
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