1. a thickened and hardened area of skin, typically caused by repeated friction or pressure
Usage: medical/anatomical
2. emotional insensitivity or hardheartedness
Usage: formal; figurative

Examples

• The guitarist developed a callosity on his fingertips from years of practice.
• Workers who handle rough materials often develop callosities on their hands.
• The doctor examined the callosity on the patient’s foot.
• His emotional callosity made it difficult for him to empathize with others.
• Years of harsh experiences had created a callosity in her heart.
• The callosity on his palm was evidence of his dedication to manual labor.