hard·​en | \ ˈhär-dᵊn How to pronounce harden (audio) \
hardened; hardening\ ˈhärd-​niŋ How to pronounce hardening (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 offharden 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 offplants hardened off before the first frost


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


biographical name (2)

Definition of Harden (Entry 3 of 3)

Maximilian 1861–1927 originally Felix Ernst Witkowski German writer

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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 But that exceptionalism can harden us to the humanity of other people and to their concerns. The Atlantic, "Listen: Serenity Now," 18 June 2020 As bystanders continued to weigh in on social media, divisions on the board seemed to harden. Rachel Swan, SFChronicle.com, "A national reckoning over police violence hits BART, again," 13 June 2020 The volatile and complex proxy war arena of Jammu and Kashmir has further helped the Indian army to battle-harden its soldiers. CNN, "Beijing's military adventurism in the Himalayas is risky. The world is big enough for the rise of India and China," 4 June 2020 Family ties strengthened, appreciations were created and hardened. Paul Daugherty, Cincinnati.com, "Paul Daugherty: This is a time for extraordinary gratitude," 19 May 2020 Refrigerate for 1–6 hours, covering with plastic wrap when chocolate shell hardens. Eric Velasco, al, "How to make simple icebox pies for summer," 7 May 2020 For some experts in nuclear issues, the year ahead now opens the door to serious discussion of ways of fortifying the NPT, particularly by hardening the consequences of member states withdrawing from the treaty, as North Korea did in 2003. Howard Lafranchi, The Christian Science Monitor, "Nuclear proliferation: How coronavirus crisis is opportunity," 23 Apr. 2020 That warning hardened a recognition in Washington that the struggle against the coronavirus will not be resolved quickly even as Trump expressed a longing for normalcy. Author: Zeke Miller, Jill Colvin, Anchorage Daily News, "After avoiding talk of death for weeks, Trump now bracing US for big toll," 30 Mar. 2020 China has become a key battleground for the 2020 election as supporters of Trump hope a hardening in public opinion offers a populist route to victory that mirrors their 2016 playbook. Rob Crilly, Washington Examiner, "Trump team hears echoes of 2016 victory emanating from China," 19 May 2020

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


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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Statistics for harden

Last Updated

3 Jul 2020

Cite this Entry

“Harden.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/harden. Accessed 8 Jul. 2020.

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More Definitions for harden


How to pronounce Harden (audio)

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


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.

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More from Merriam-Webster on harden

Thesaurus: All synonyms and antonyms for harden

Rhyming Dictionary: Words that rhyme with harden

Spanish Central: Translation of harden

Nglish: Translation of harden for Spanish Speakers

Britannica English: Translation of harden for Arabic Speakers

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