altération

Altération is a French noun derived from the verb altérer. It designates the action of altering something, that is, changing its nature, quality, state, or appearance. The term can imply a partial or complete transformation and is often used with a negative connotation, such as degradation or corruption. In everyday language, altération appears in expressions referring to altered data, altered documents, or altered states of being, among others.

In scientific contexts, the term is most common in geology and materials science. Geology uses altération to describe weathering processes that modify rocks at or near the surface, through physical (mechanical) and chemical mechanisms. Physical weathering includes frost action, thermal expansion, and abrasion, while chemical weathering encompasses hydration, hydrolysis, oxidation, and dissolution. In materials science, altération refers to the deterioration of materials due to environmental exposure, including corrosion, wear, or chemical attack, which can affect mechanical properties and longevity.

In medicine and biology, altération denotes impairment or dysfunction of a function or organ, such as altération de la conscience or altération des résultats biologiques. The term is also used in data management to indicate alteration of information, whether intentional or accidental, compromising integrity or authenticity.

Linguistically and musically, altération can describe modification of a phoneme or of a pitch, respectively, such as the use of accidentals (dièse, bémol) that alter a note’s height. Overall, altération is a versatile term for any change that moves something away from its original state.