Definition of harden
(Entry 1 of 3)
1 : to make hard or harder
2 : to confirm in disposition, feelings, or action especially : to make callous hardened his heart
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)
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
Harden
biographical name (1)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
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Time Traveler for harden
The first known use of harden was in the 13th century
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