Abrasion has several definitions in the field of
medicine. One definition is a tearing off, wearing off, or
circumscribed removal of the top layers of skin or
mucous membrane. A mucous membrane is one of four
major types of thin sheets of tissue that line or cover
various parts of the body. This definition of abrasion is
also known as an abraded wound.

A second definition of abrasion is a scraping away of a
part of the surface.
An abrasion of the knee.
FEATURED BOOK: Wounds and Lacerations: Emergency Care and Closure

A third definition of abrasion occurs in dentistry and refers to the abnormal grinding or
wearing away of a tooth substance by improper tooth brushing methods, the presence of
foreign bodies, bruxism (clenching or grinding the teeth), or similar causes. This definition
of abrasion is also known as grinding.

There are other words related to abrasion that you may come across. For example,
abrade means to wear away by mechanical action or to scrape away part of a surface
layer or all of a surface layer from something. Abrasive means a) causing abrasion, b)
any material used to produce abrasion, and c) a substance used in dentistry to abrade,
polish, or grind. Abrasiveness means the property of a substance that causes wear of a
surface by friction (resistance when one substance contacts another).
Abrasiveness also means the quality of being able to wear away another material or
scratch it. Abrasion (and the related words noted above) comes from the Latin word
“abrasus” meaning “to scrape off.”
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