When an online merchant or service provider seemingly disappears after failing to hold up his end of the deal.
"I paypal'd that guy on eBay his fifteen bucks three weeks ago, I haven't gotten the merchandise and he's not answering my email. I'm getting nothing but webair."
A trip to a grocery store, convenience store, or gas station for the sole purpose of buying an excessive amount of junk food and sugary drinks, usually with friends. A chud run often happens late at night and ends with everyone involved hating themselves afterwards.