a fusion of 'by accident' and 'on purpose' meaning to accidently do something on purpose. To acknowledge that ones actions were deliberate whilst at the same time claiming there was an unintentional component – in other words a feeble plea of mitigation.
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.