- 1[intransitive, transitive] to become or make something become firm, stiff or solid The varnish takes a few hours to harden. harden something a method for hardening and preserving wood
- 2[intransitive, transitive] if your voice, face, etc. hardens, or you harden it, it becomes more serious or severe Her face hardened into an expression of hatred. harden something He hardened his voice when he saw she wasn't listening.
- 3[intransitive, transitive] if somebody’s feelings or attitudes harden or somebody/something hardens them, they become more fixed and determined Public attitudes to the strike have hardened. Their suspicions hardened into certainty. Opinion seems to be hardening against the invasion. harden something The incident hardened her resolve to leave the company.
- 4[transitive, usually passive] harden somebody/something/yourself to make somebody less kind or less affected by extreme situations Joe sounded different, hardened by the war. They were hardened criminals (= they showed no regret for their crimes). In this job you have to harden your heart to pain and suffering. Life has hardened me. I need to harden myself against disappointment. Extra examples His expression suddenly hardened into one of strong dislike. Leave the icing to harden in the fridge. When the paint has hardened thoroughly, you can apply the next coat.
BrE BrE//ˈhɑːdn//; NAmE NAmE//ˈhɑːrdn//Verb Forms present simple I / you / we / they harden
BrE BrE//ˈhɑːdn//; NAmE NAmE//ˈhɑːrdn//he / she / it hardens
BrE BrE//ˈhɑːdnz//; NAmE NAmE//ˈhɑːrdnz//past simple hardened
BrE BrE//ˈhɑːdnd//; NAmE NAmE//ˈhɑːrdnd//past participle hardened
BrE BrE//ˈhɑːdnd//; NAmE NAmE//ˈhɑːrdnd//-ing form hardening
BrE BrE//ˈhɑːdnɪŋ//; NAmE NAmE//ˈhɑːrdnɪŋ//