ok, well this isn't the one I was thinking of, but it's another and it'll have to do for the time being...
when you write a word and it just doesn't look right
I had this happen recently with the word "inscrutable" - - even after I looked it up to verify the spelling, it still looked wrong...
another one - this is dedicated to the good Dr. Jones...
mispell - - misspell
It looks wrong no matter what!
but somehow, when you put it in the past tense, it looks OK
misspelled