callus

[kal-uh s]

See more synonyms for callus on Thesaurus.com

noun, plural cal·lus·es.

Pathology, Physiology.
1. a hardened or thickened part of the skin; a callosity.
2. a new growth of osseous matter at the ends of a fractured bone, serving to unite them.
Also callose. Botany.
1. the tissue that forms over the wounds of plants, protecting the inner tissues and causing healing.
2. a deposit on the perforated area of a sieve tube.
3. (in grasses) a tough swelling at the base of a lemma or palea.

verb (used without object), cal·lused, cal·lus·ing.

to form a callus.

verb (used with object), cal·lused, cal·lus·ing.

to produce a callus or calluses on: Heavy work callused his hands.

Origin of callus

1555–65; < Latin callus, masculine variant of callum; see callous

Related formsun·cal·lused, adjective

Can be confusedcallous callus

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for callus

Historical Examples

There's naething in the whiskey to prevent the proper formation of callus.
Charles O'Malley, The Irish Dragoon, Volume 2 (of 2)
Charles Lever
The callus of the third glume is short, pointed and villous.
A Handbook of Some South Indian Grasses
Rai Bahadur K. Ranga Achariyar
The callus is long, acute, bearded with reddish-brown hairs.
A Handbook of Some South Indian Grasses
Rai Bahadur K. Ranga Achariyar
There was also some callus on the posterior surface of the lower end of the humerus.
Castes and Tribes of Southern India
Edgar Thurston
The formation of callus in fractured limbs was also increased.
Poisons: Their Effects and Detection
Alexander Wynter Blyth

British Dictionary definitions for callus

callus

noun plural -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
1. a mass of hard protective tissue produced in woody plants at the site of an injury
2. 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

Word Origin

C16: from Latin, variant of callum hardened skin

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for callus

n.

"hardened skin," 1560s, from Latin callus, variant of callum "hard skin," related to callere "be hard," from PIE root *kal- "hard" (cf. Sanskrit kalika "bud," Old Irish calath "hard," Old Church Slavonic kaliti "to cool, harden").

callus in Medicine