callous (adj) - unfeeling, indifferent, or inured to pain and suffering [kal-uhs]
callus is a hardened, thickened patch of skin,
callousness is heartlessness or insensitivity
BREAKDOWN: The word callous represents a figurative application of the concept of a physical callus: thick skin that minimizes feelings of pain. Both words derive from the Latin callus meaning hard skin.
“If I’ve thought of my mother as callous, and many times I have, then it is important to remember what a callus is: the hardened tissue that forms over a wound.” —Yaa Gyasi
[Our Wednesday Wildcards are fascinating and important words that are not necessarily derived from classical roots.]