abbreviation
n//əˌbɹi.viˈeɪ.ʃn̩//förkortning, förkortande
(linguistics) A shortened or contracted form of a word or phrase used to represent the whole, using omission of letters, and sometimes substitution of letters, or duplication of initial letters to signify plurality, including signs such as +, =, @. [Late 16th century.]
(mathematics) Reduction to lower terms, as a fraction.