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: ...Oh, come on. That was funny.
This is wat u say when a joke obviously isnt funny and u want the other person to kno it
tard: HEY WHY DID THE CHICKEN CROSS THE ROAD?
tard: TO GET TO THE OTHER SIDE!
you: *crickets chirp*