Definition of harden
hardeningplay \ˈhärd-niŋ, ˈhär-dən-iŋ\
1 : to make hard or harder
2 : to confirm in disposition, feelings, or action; especially : to make callous hardened his heart
4 : to protect from blast, heat, or radiation (as by a thick barrier or placement underground)
1 : to become hard or harder
2a : to become firm, stable, or settledb : 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 of harden from the Web
Then, someone came up with the idea to add a nonsolvent, which would not dissolve into the glue and would keep it from hardening.
In a sign of the Trump administration's hardening stance on that issue, the Treasury Department on Thursday blacklisted a Chinese bank accused of conducting millions in illicit business with North Korea.
ARTERIAL STIFFNESS The combination of damage, clogging and hardening can lead to arterial stiffness.
Track and field and cycling, also ensnared in the scandal but more hardened by past entanglements, have been less haughty, a caution borne out by subsequent incidents.
Microsoft's EMET, the Enhanced Mitigation Experience Toolkit, was a useful tool for hardening Windows systems.
The field trial is intended to use sunlight, rather than temperature, to stress and harden the corals against bleaching.
Among white women in particular, views of Trump in Quinnipiac polling are hardening.
Despite the obvious importance of verifying shock-hardening, the Navy changed its rules in 2013.
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.
First Known Use of harden
Definition of Harden
Sir Arthur 1865–1940 English chemist
Definition of Harden
Maximilian 1861–1927 originally Felix Ernst Witkowski German writer
HARDEN Defined for English Language Learners
Definition of harden for English Language Learners
: 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 Defined for Kids
Definition of harden for Students
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.
Seen and Heard
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