Just like the name implies, a cock that's oblong. It is thick at the tip, from which the shaft tapers to the base, much like a Louisville Slugger.
"I watched a video of this hot bitch brushing her teeth, in the nude, which was great until the camera panned down to show the he/she's oblong schlong whirling around like a propeller. The horror! The horror!"
by Nosefuckers Incorporated December 14, 2012