The noise generated deep in the bowels when you're holding in a fart. This usually happens in large groups and/or close quarters with other individuals. The sound is quite similar to the underwater calls of the blue whale, which can include clicking noises and long, soulfull groans. Individuals engaged in whale calling will often blame hunger, and that the noise is a "growling" stomach, but the astute observer should readily identify the sound as flatulence desperate to escape the confines of the "caller's" bowels. The whale call may also be referred to as a "reverse-fart".
Denise (upon whale calling): Oh my, I'm so hungry my stomach is growling!
Fritz: Bullshit, it's 2pm and you just ate...you're whale calling because you probably have to take a dump.