It's like "gesundheit" but for when someone coughs. I tend to feel like saying something when someone coughs. A powerful cough is similar enough to sneezing (if slightly more voluntary) that it should have a word, too.
Mark: *Cough!*
Ashley: Coughsundheit, my son, coughsundheit.
Mark: What the heck?
by Mary Ann Brennan April 26, 2006
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