What do you call words that are typed the same way on a phone keypad?

A numeronym is a word which is sometimes spelled using numerals.¹ It was originally a term for a telephone number having an alphanumeric meaning. Here are some illustrative examples of different types of numeronym.

• 800-DIGITAL (344-4825, once the toll-free number for the legendary computer company)² – A telephone number having an alphanumeric meaning: the original use of numeronym was for such numbers.

• 4#26#4663, pronounced I AM HOME (or I AM GONE) – Using symbols on a telephone keypad to spell words. Notice how this example shows that predictive texting technology can lead to ambiguities. Slang terms are also developing for such ambiguities, such as “textonym” and “tynonym”.³

• i18n, pronounced internationalization – Abbreviation using numerals to represent the number of omitted letters.⁴

• K9, pronounced canine – Abbreviation using numerals to represent the sound of omitted letters.⁵

• l33t, pronounced leet (slang for elite) – Using numerals which resemble letters they replace.⁶

• 07734, pronounced hello – Using numerals which (upside down) resemble letters they replace, also known as beghilos or “calculator spelling”.⁷

• G8 and Y2K, pronounced gee-eight and wye-two-kay – Words originally coined using numerals.⁸