Pronunciation: (kal'us), [key]
—n., pl. -lus•es,
—v., -lused, -lus•ing.
1. Pathol., Physiol.
a. a hardened or thickened part of the skin; a callosity.
b. a new growth of osseous matter at the ends of a fractured bone, serving to unite them.
2. Also,callose. Bot.
a. the tissue that forms over the wounds of plants, protecting the inner tissues and causing healing.
b. a deposit on the perforated area of a sieve tube.
c. (in grasses) a tough swelling at the base of a lemma or palea.
to form a callus.
to produce a callus or calluses on: Heavy work callused his hands.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.