harden

Definitions

• (intransitive) To become hard (tough, resistant to pressure).
• (transitive) To make something hard or harder (tough, resistant to pressure).
• (transitive) To strengthen.
• (transitive) To modify (a website or other system) to make it resistant to malicious attacks.
• (ambitransitive) To become or make (a person or thing) resistant or less sensitive.
• (ambitransitive) To become or make (a consonant) more fortis.