Tonight my five-year-old made up a great new word: SCUMQUAT! It's hilarious, and while he didn't intend it to be anything more than a word for something yucky, it's been instantly coined as a household term.
We were playing "yucky soup," a very juvenile sort of game that's inventive and funny and amuses the kid much longer than strictly necessary. You come up with all the yucky, funny things you can think of to add to the most horrible imaginary soup there is. Nothing too dark, just super-duper-yucky: dog fur, boogers, dirty socks, ear wax, decayed sausages, etc. But he gets carried away after a while and start making things up once he's run out of concretely yucky ingredients. Hence the Scumquat.
Oh, I foresee trouble once kindergarten commences. You scumquat. Eew!