hardened

Hardened is the past participle of harden and is used as an adjective to describe something that has been made harder, stiffer, or more resistant to wear, damage, or decay. The term is applied across disciplines to indicate increased durability, strength, or rigidity, or to describe a state that has become fixed or unyielding.

In materials science and manufacturing, hardening refers to processes that increase hardness or strength. In metals, heat treatments such as quenching and tempering or case hardening create a harder surface and improved wear resistance. Hardened concrete or ceramics refers to mixtures or products that have attained additional strength and durability through curing or sintering, while glass can be tempered to improve strength and impact resistance.

In computing and information security, hardening describes configuring software, operating systems, and networks to reduce vulnerabilities and minimize attack surface. Practices include applying security patches, disabling unused services, enforcing least privilege, configuring firewalls, and auditing configurations. A hardened system is intended to be less susceptible to compromise, though it may involve trade-offs in usability.

In biology and medicine, hardened describes tissues that have become rigid, such as hardened arteries (arteriosclerosis) or fibrotic tissue. The term can also appear in everyday language to describe objects that have dried or calcified over time.