This is a tissue made of undifferentiated cells produced by rooting hormones on plant cuttings. A callus arises from cells of the cambium. When a callus forms, some of its cells may organize into growing points, some of which in turn give rise to roots while others produce stems and leaves.
This article is missing information about evolution and biology. (July 2019) |
A callus (pl.: calluses) is an area of thickened and sometimes hardened skin that forms as a response to repeated friction, pressure, or other irritation. Since repeated contact is required, calluses are most often found on the feet and hands, but they may occur anywhere on the skin. Some degree of callus, such as on the bottom of the foot, is normal.
| Callus | |
|---|---|
 | |
| Examples of callus found on the toe | |
| Specialty | Dermatology |
| Complications | Skin ulceration, infection |
Calluses are generally not harmful and help prevent blisters, as well as offering protection. However, excessive formation may sometimes lead to other problems, such as a skin ulceration or infection, or cause the affected person to try to offload the affected painful area, which can place excessive stress on the asymptomatic side.
Rubbing that is too frequent or forceful will cause blisters, as opposed to calluses, to form.
English
Etymology
Borrowed from Latin callum (“hard skin”). Displaced native Old English wearr.
Pronunciation
- (General American, UK) IPA(key): /ˈkæləs/
- Rhymes: -æləs
- Homophone: callous
Noun
callus (countable and uncountable, 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
