What word is spelled incorrectly in every dictionary?

How to think about it

1. Dictionaries are checked carefully, so no ordinary word is misspelled in all of them. The riddle must mean something else.
2. Reread the question and look for a word that is being used as itself.
3. The word “incorrectly” is spelled i-n-c-o-r-r-e-c-t-l-y in every dictionary.
4. So “incorrectly” is the word that is spelled “incorrectly” everywhere.

Why “Incorrectly” is the answer

Every dictionary spells the word “incorrectly” the same way, so in a literal sense that word is always spelled incorrectly. The riddle depends on reading “spelled incorrectly” as a quotation rather than a judgment. It belongs to a family of self-referential puns that includes “what word is always pronounced wrong”.

Common wrong answers

• Misspelled. A tempting cousin, but the riddle names the exact word in its own text, and that word is incorrectly.
• Wrong. That is the answer to a different riddle about pronunciation.