Used to point out or emphasise silence. (Well, not precisely silence, since chirping crickets make sound. But you get it.)
The idea is that you can only hear crickets when there are no other sounds, such as conversation or laughter. Often used to denote the awkward pause after a bad joke.
Joe: What's the sound of two drums and a cymbal falling over a cliff?
Ted: *tiredly* I don't know, Joe. What is the sound of two drums and a cymbal falling over a cliff?
Joe: baDUM-ksh!
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.