Callus

Pathology, Physiology.

a hardened or thickened part of the skin; a callosity.
a new growth of osseous matter at the ends of a fractured bone, serving to unite them.

Also, callose. Botany.

the tissue that forms over the wounds of plants, protecting the inner tissues and causing healing.
a deposit on the perforated area of a sieve tube.
(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.
Historical Examples

The Nursery Book Liberty Hyde Bailey
A Handbook of Some South Indian Grasses Rai Bahadur K. Ranga Achariyar
Northern Nut Growers Association Report of the Proceedings at the Various
A Handbook of Some South Indian Grasses Rai Bahadur K. Ranga Achariyar
Disease in Plants H. Marshall Ward
Poisons: Their Effects and Detection Alexander Wynter Blyth
Special Report on Diseases of the Horse United States Department of Agriculture
American Pomology J. A. Warder
The Little Gleaner, Vol. X. Various
Manual of American Grape-Growing U. P. Hedrick

noun (pl) -luses
Also called callosity. an area of skin that is hard or thick, esp on the palm of the hand or sole of the foot, as from continual friction or pressure
an area of bony tissue formed during the healing of a fractured bone
(botany)

a mass of hard protective tissue produced in woody plants at the site of an injury
an accumulation of callose in the sieve tubes

(biotechnology) a mass of undifferentiated cells produced as the first stage in tissue culture
verb
to produce or cause to produce a callus
n.

callus
(kāl’əs)