(anatomy) a broad band of nerve fibers joining the two hemispheres of the brain

(literary) hardened skin on the hands or feet caused by friction or hard labor

Literally having calluses on hands and feet; describes extremely hard work or a life of toil over a long period.

(literary) hands and feet covered in calluses; used to describe working extremely hard and enduring great toil

(idiom) hands and feet covered in calluses; describes someone who has been working extremely hard or performing grueling physical labor