God! That's tough. One can step back from someone who has bad breath. Or, play it off by offering some mints or gum, blaming your own bad breath to something you ate. But, I've bumped into some people who's B-O was so strong, it lingered after they left! So, I guess it would have to be body odor. You can close your mouth, and write down what ever you have to say, but B-O is in a class of its own! You just can't correct it immediately.