You mistype a word. You make a "finger check". You accidentally transpose letters typing too fast, or from muscle memory.
A spelling checker does not recognize your typo because your incorrect typing resulted in a correctly spelled (though wrong and unintended) word.
Only careful human reading (or maybe very sophisticated context analysis) will catch this mistake of a word that was not intended to be used.
What is the term for such a 'misspelling' (or this specific class of typographical error)?
People have argued that by definition, the mistyping is not a misspelling. This makes talk about locating these errors even more difficult because of the ambiguity of "spelling error" in this context.
What term would you use when requesting an editor to specifically look for this "misspelling but not a misspelling" class of error?