The sound accompanying a completely liquid bowel movement. There is no gas, the sound just reverbs through the liquid. Not to be mistaken with a fart, a lirf is not from gas. It was once gas but when it mixed and churned with the liquid they became one. You can also feel the difference. We all know the fart, but a lirf is something special. It can be felt deep within the intestine, as the sound is with your whole body, not just blowing out your ass. Some find it pleasant, others feel sick, though on occasion there can be some intense intestinal distress afterwords. The opposite of a lirf is a Panda's Whisper, where you manage to complete the bowl movement without a sound.
He's in the upstairs bathroom, I'm in the kitchen, yet i could tell he has some pretty bad diarrhea because his lirfs made the walls vibrate.

With every squirt i could feel the lirf growling through my bones.
by Chicken nuggets with Ranch November 5, 2013
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