1. (noun)World-wide, this is the most recognized word meaning "Shit."
More recently, it has been used as a deragatory word referring to those informants who tell your girlfriend things you've done or said that you never wanted her to know. When she gets this information, the shit starts to fly.
As a verb, it is used as the aforementioned act of informing the girlfriend that causes the shit to fly. It is also used as a verb referring to the shit flying.
Ellen is such a caca. She told my girlfriend Mary all about the time I lied and said I was working late so I could go out with the guys to the titty bar. She really cacaed my life for weeks. Damn caca.