A word Sunmi (순미) uses in her song Gashina (가시나). No one knows what the fuck the word means, but, look on the bright side - everyone knows the dance to Gashina.
The title of a song by Kpop idol Sunmi it is also used as a word in the song itself. There is a dance of which accompanies the song where gun fingers are used and you move your head from side to side.
“wae yeppeun nal dugo gashina” is the line in Korean used in the song gashina
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.