Mine is blah, blah blah...."my friend" spoken by anyone that is not my friend.
This is a phrase that is endearing when spoken between true friends, but used to rope someone in to whatever is being talked about is a huge turn off to me. When I mentioned it to DH, he also said that it is an immediate distancing or beware sign for him, when spoken by those other than friends.
So what is the phrase or word that you do not care for?