F.U.I.H. stands for fuck you im high. Used in order to refuse a request of action or even movement; while also reasoning for being forgetful while under the effects of Marijuana.
**(usually used in digital communication such as Facebook, texting etc...)
It's supposed to be used jokingly (please dont kill people..it's not nice)
It's explained in its self.. not much else I can say.
You've been my b.f.u.i.k.y for almost 5 years, and although you can piss me off occasionally, your the coolest person I've ever met and I love you bro, you're not LIKE my sister, you ARE my sister..