- a hardened, thickened place on the skin
- the hard substance that forms at the break in a fractured bone and serves to reunite the parts
- a disorganized mass of cells that develops over cuts or wounds on plants, as at the ends of stem or leaf cuttings
Origin of callusL, variant, variety of callum, hard skin
to develop or cause to develop a callus
- a. A localized thickening and enlargement of the horny layer of the skin. Also called callosity.b. The hard bony tissue that develops around the ends of a fractured bone during healing.
- Botany a. Undifferentiated tissue that develops on or around an injured or cut plant surface or in tissue culture.b. The hardened, sometimes sharp base of the spikelet of certain grasses.
intransitive verbcal·lused, cal·lus·ing, cal·lus·es
To form or develop such hardened tissue. See Usage Note at callous.
Origin of callusLatin, masculine of callum.
(plural calluses or calli)
- A hardened area of the skin (especially on the foot or hand) caused by repeated friction, wear or use.
- The material of repair in fractures of bone; a substance exuded at the site of fracture, which is at first soft or cartilaginous in consistency, but is ultimately converted into true bone and unites the fragments into a single piece.
- (botany) The new formation over the end of a cutting, before it puts out rootlets.
(third-person singular simple present calluses, present participle callusing, simple past and past participle callused)
- (intransitive) To form such hardened tissue