Often said by people to bully 12 year old boys with below average penises. Basically, if you know any 12 year old boys that like trump, wear neon clothes, act gay but arent gay and have a ''J'' name, make sure to remind them it's very small and nobody will ever fuck them.
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.