harden

• 动词，表示使某物变硬、变坚固或更稳定，也指变得无情、严厉或更坚定。

A verb used to indicate the process of becoming or making something hard, solid, or resistant, or of becoming less sympathetic or more severe.

1. Become solid or firmB1formal

   To become physically hard or solid, or to make something become hard.

   变硬

   • The cement will harden within a few hours.
   • Allow the glue to harden before moving the pieces.
   • The lava hardened into rock as it cooled.

   同义词cakeclotcongealfreezesetsolidifystiffenthicken

   反义词dissolveliquefymeltsoften

2. Become tough or unfeelingB2formal

   To become more severe, strict, or less sympathetic.

   变得冷酷

   • Years of disappointment hardened his heart.
   • The government hardened its stance on immigration.
   • She hardened herself against the criticism.

   同义词callousdesensitizeindurateinuretoughen

   反义词mellowrelentsoften

3. Strengthen or reinforceB2formal

   To make something stronger or more resistant.

   加强

   • The company hardened its security protocols after the breach.
   • Regular exercise hardens the muscles.
   • They hardened the steel to make it more durable.

   同义词annealfortifyreinforcesolidifysteelstiffenstrengthentempertoughen

   反义词debilitatesoftenundermineweaken