To day I learned it's called numeronyms they seems to be very infrequent out side of slang/tech, these are all words I think you should just know around here: I18n A11y l10n Y2K 420 a16z
If you are into making software for something more than just the naive "one market" your first introduction would be internationalization which should be the most widespread. When you make things for government in the EU/US you will most probably have laws demanding accessibility features. The problem isn't the numeronym but that so few people care about accessibility.
