Definition of "harden" in English

verb

1. (intransitive) To become hard.

2. (transitive, ergative) To make something hard or harder.

3. (transitive, figurative) To strengthen.

4. (transitive, computing) To modify (a website or other system) to make it resistant to malicious attacks.

5. (ambitransitive) To become or make (a person or thing) resistant or less sensitive.

   • When thou goest to return into Egypt, see that thou do all those wonders before Pharaoh, which I have put in thine hand: but I will harden his heart, that he shall not let the people go.

6. (intransitive, informal) To get an erection.

7. (ambitransitive, phonology) To become or make (a consonant) more fortis; to (cause to) undergo fortition.

8. (Slavic phonology) To unpalatalize or velarize.

noun

1. Alternative form of hurden (“coarse linen”).