harden

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

Definition of harden

 (Entry 1 of 3)

transitive verb

1 : to make hard or harder
2 : to confirm in disposition, feelings, or action especially : to make callous hardened his heart
3a : 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
2a : 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

Harden

biographical name (1)
Har·​den | \ ˈhär-dᵊn How to pronounce Harden (audio) \

Definition of Harden (Entry 2 of 3)

Sir Arthur 1865–1940 English chemist

Harden

biographical name (2)

Definition of Harden (Entry 3 of 3)

Maximilian 1861–1927 originally Felix Ernst Witkowski German writer

Synonyms & Antonyms for harden

Synonyms: Verb

Antonyms: Verb

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Examples of harden in a Sentence

Verb 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.
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Recent Examples on the Web: Verb Each one of them was the historical equivalent of a chemical phase change—when water, say, grows hot enough to sublime into steam or cold enough to harden into ice. Jeffrey Kluger, Time, 11 July 2021 Sea levels lowered, leaving shells, coral and sediments to harden into limestone. Patrick Connolly, orlandosentinel.com, 20 June 2021 VanTrece likes to do this while the skillet is still warm, before the grime gets a chance to harden or get crusty. Marygrace Taylor, SELF, 6 Nov. 2021 After Fredericks spends time at a Buddhist monastery in Kyoto, Japan, in 1966, his exploration of Buddhism deepens, and his daily entries harden to the world, growing formalized and solipsistic. Benjamin Anastas, The New Yorker, 1 Nov. 2021 The team noted that the process to harden the wood was far more energy-efficient than making other materials. Jordan Mendoza, USA TODAY, 27 Oct. 2021 As a result, the Pentagon must harden National Security Systems against outside threats, particularly cyberattacks. Kyle Mizokami, Popular Mechanics, 12 Oct. 2021 Officials have expressed confidence that efforts to harden levees and flood systems around New Orleans after Hurricane Katrina would be enough to hold back storm surges. New York Times, 29 Aug. 2021 Psaki acknowledged Tuesday that administration officials are aware of the risk that Biden's support for vaccine mandates could harden opposition to vaccines among his detractors. Alexandra Jaffe, Star Tribune, 27 July 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'harden.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of harden

Verb

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

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Time Traveler for harden

Time Traveler

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

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Dictionary Entries Near harden

hard-edged

harden

Harden

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Statistics for harden

Last Updated

25 Nov 2021

Cite this Entry

“Harden.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/harden. Accessed 30 Nov. 2021.

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More Definitions for harden

harden

verb

English Language Learners Definition of harden

: to become hard or firm or to make (something) hard or firm
: to become more definite and strongly felt or to make (something) more definite and strongly felt
: to make (someone) hard : to make (someone) less emotional and less likely to feel sorry for other people

harden

verb
hard·​en | \ ˈhär-dᵊn How to pronounce harden (audio) \
hardened; hardening

Kids Definition of harden

1 : to make or become hard or harder By now the cement has hardened.
2 : to make or become hardy or strong Years of tough work had hardened his muscles.
3 : to make or become stubborn or unfeeling She hardened her heart and refused to forgive him.

More from Merriam-Webster on harden

Nglish: Translation of harden for Spanish Speakers

Britannica English: Translation of harden for Arabic Speakers

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