Definition

That morning-after panic when you wake up feeling like garbage and irrationally convince yourself you've contracted swine flu, only to realize it's just a hangover with extra paranoia. The imaginary illness that strikes the morning after over-enthusiastic wine consumption.

Example Usage

I woke up feeling like death warmed over and was convinced I had the plague, but my friend was like 'Dude, that's just wine flu from last night.'

Source: Urban Dictionary (https://www.urbandictionary.com/define.php?term=wine%20flu&defid=3925631)