The definition of typo, according to Cambridge Dictionary:
a small mistake in a text made when it was typed or printed
Can anyone tell me the long form of typo?
The definition of typo, according to Cambridge Dictionary:
a small mistake in a text made when it was typed or printed
Can anyone tell me the long form of typo?
Typo is short for "typographical error".
From Dictionary.com:
noun, plural ty·pos.Informal.
typographical error.
I advocate typing error for present-day usage.
This better than typographical error reflects what is used in other languages, for example German Tippfehler, French erreur de frappe (or faute de frappe), Danish tastefejl (literally keying error).
It’s also the meaning that I have always understood from typo: an error made in typing.
Obviously, if what you intended was an error in the typography without regard to how that error has come about, then you should say that: typographical error.
Edit: PC Luddite commented:
This may be a more accurate description of what a typo is, but it doesn't explain its origin.
I get your point. Maybe I interpreted the question of the long form of “typo” a bit differently from you. I agree that origin is relevant, though. So let’s take it, here from Online Etymology Dictionary (link at the bottom):
1816, "compositor," short for typographer; 1892 as short for typographical error
My interpretation was more, when people use typo in 2022, what would be the long form? So I answered what I think people mean by it today, not what they meant more than 100 years ago.