A numeronym is a word, usually an abbreviation, composed partially or wholly of numerals. The term can be used to describe several different number-based constructs, but it most commonly refers to a contraction in which all letters between the first and last of a word are replaced with the number of omitted letters (for example, "i18n" for "internationalization").[1] According to Anne H. Soukhanov, editor of the Microsoft Encarta College Dictionary, it originally referred to phonewords – words spelled by the letters of keys of a telephone pad.[2]
A numeronym can also be called an alphanumeric acronym or alphanumeric abbreviation.