Definition of the word hardness

The word "hardness" has its roots in Old English, where it was spelled as "hardnæss" or "hardnes". The term referred to the physical quality of being resistant to pressure, scratching, or penetration. This sense of the word is derived from the Proto-Germanic word "*hardiz", which is also the source of the Modern English word "hard". Over time, the meaning of "hardness" expanded to include figurative senses, such as strength of character, firmness of purpose, or the quality of being difficult to handle or manage. In the 14th century, the word also took on a scientific connotation, referring to the resistance of a material to being deformed or damaged. Today, "hardness" is used in various fields, including geology, materials science, and physics, to describe the physical properties of materials, as well as in idiomatic expressions, such as "hardness of heart" or "hardness of life". Despite its evolution, the core meaning of "hardness" remains tied to its ancient roots in physical resistance.