From NPR

[John Cole]

One of my favorite local NPR programs is Says You (or Sez You)--it's radio so I don't know how they spell it. The contestants are given a word which, in all probability, nobody will know and supply the other team with one real definition and two phonies. Tonight's word, "ylem," was defined by one panelist as the simplest explanation possible for any action or occurence. As an example, he offered this: Why do scuba divers fall backwards into the water?

Answer: if they fell forwards, they'd still be in the boat.

BTW, the only word I've ever known was "patzer." Thank you Searching for Bobby Fischer.

[Oski]

Sounds funny! Reminds me of one of my favorite games called "Balderdash." Follows pretty much the same format.

[stripsqueez]

i've played this game for beers - all time favourite phony answer "small european fish"

stripsqueez - chickenhawk

[Paddy]

Says You is a brilliant game. Definitely my favorite show on the radio.

[TimM]

I've seen this word used before in cosmology:

"y·lem - noun

primordial matter: hypothetical matter that, according to the big bang theory of the origin of the universe, was the substance from which the chemical elements were formed."

From what I've read it was more commonly used to mean something like the "egg" the universe "hatched" from. Of course the actual definition was given as well, to show the reason for it's use.