The act of calling your friends while taking a dump. Usually happens after large meals of the Mexican genre. The dump dialer usually forgets the phone call and or regrets the phone call in the morning.
Oh man I really gotta stop dump dialing when I'm eating.
Dude you dump dialed me last night?
calling your buddy from the can to brag about the fecal masterpiece you just created. also, why camera phones were invented
*ring* *ring* - "hello?", "hello?"
--"dude what's that echo, are you dump dialing me?"
"ohhh yeah, I just shat out a mag-lite and I need a ride to the hospital"
When one person is on the toilet for a at least 8 minutes, taking a crap, calls another on their phone from the toilet.
Unlike when someone butt-dials you or drunk-dials you, DUMP DIALS mostly occur sober, and on purpose.
"Hey bro, sorry to DUMP DIAL you, but i had to call you from the can...I'm getting a blumpkin!!!!"