k.y.d.k.s
K. Y. D. K. S. is when you're a kid and you're so dumb that people shout it at you like it's a battle cry.
My sister said, 'K. Y. D. K. S.!' when I tried to explain why the moon changes shape.
My dad said, 'K. Y. D. K. S.!' after I tried to fix the TV and it started playing baby videos.
My teacher wrote, 'K. Y. D. K. S.!' on my science test after I said plants drink coffee.