The word "calloused" refers to skin that has become tough and thick due to repeated friction or pressure. Some synonyms for "calloused" include "hardened", "thickened", "coarse", "rough", and "toughened". Other similar words that can be used interchangeably with "calloused" include "roughened", "leathery", "firm", "unyielding", "unfeeling", and "stiff". These synonyms are often used to describe physical objects or tangible things that have become tough and durable over time. However, "calloused" can also be used to describe someone's personality or behavior, such as a calloused attitude towards others, which suggests a lack of compassion or empathy.