Pronunciation: (kal'us), [key]
1. made hard; hardened.
2. insensitive; indifferent; unsympathetic: They have a callous attitude toward the sufferings of others.
3. having a callus; indurated, as parts of the skin exposed to friction.
to make or become hard or callous.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.