A fart that you successfully keep from escaping but decides to let loose inside and resembles your stomach growling loudly but clearly is not coming from your stomach.
I held that fart in but everyone still heard my butt growl. I was so embarrassed when my butt growled in the middle of class.
While our lifespan is the number of years we will live, our healthspan is the number of healthy years we will have and our sexspan is is the number of years we will continue to be healthy enough to continue having an active sex life.
A lighthearted reaction upon receiving disappointing news of some sort. Usually something that isn't a particularly a big deal, esp. when it primarily affects someone else - sort of a mild schadenfreude. Sometimes doubled or tripled, and possibly said in a sing-songy voice for added comedic effect to imitate a muted trumpet, which is how the meme originated.