Do you mean "concomitant"?

"concommitant" is a common misspelling of "concomitant"

How to remember the correct way to spell "concomitant":

An exception to the rule that "o" is followed by a double "m" when the syllable "omm" is stressed.

Test your Spelling • Common Misspellings • Terms of Use • Top Ten Misspellings • Contact DoYouMean