(Can be used in other senses, but im just explaining this one)
From Doctor who.
Timelords have the ability to regenerate after severe trauma or natural wear and tear. Their body will under go a complete transformation, and although the same person remains, their appearance and personality changes. (In other words, where a human would die, a Timelord would just change, thereby healing any injury in the process.)However a Timelord only has the ability to do this 13 times. (Doesnt matter much to them, in one life they Usually live to about a thousand anyway. Notice I said usually.)
The Doctor: I'd like to see a butterfly fit into a chrysalis case after it spreads its wings.
Polly: Then you did change.
The Doctor: Life depends on change, and renewal.
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.