Like a thing-a-ma-bob, something that you don't know what else to call it.
Can be used as a derisive term for a person in the sense that you're calling them a "thing".
What's a dweed? (Lots of giggling)
A completely farcical documentary, which is intended to be viewed as a comedy.
"This is Spinal Tap" and "Fear of a Black Hat" are two examples of a mockumentary.