>As [a different] Rich said, using the word "screw" is not a good example of English grammar, however, it is often applied in speech as you mentioned. For instance, if something is not working correctly (such as computer hardware for instance) we often say that it is 'screwy' as in: "There's something screwy here" or "This is really screwed up." Also, we used it to mean the same as 'stabbed in the back' too as in: "He was really screwed by his boss" which of course derives from the sexual connotation of the word but I'm sure you get the meaning in that phrase.

Oh boy. A discussion of U.S. English slang and history of (natural) language development. I can't help but stick my US$.02 in...

I want to make a distinction between the uses Tracy mentioned for the word "screw." There's the vulgar reference to the sex act, such as "he got screwed" meaning someone was treated badly.

But the phrase that someone is screwy doesn't derive from the vulgar sexual reference, it comes from an older saying that a crazy person "has a screw loose" (in their head), meaning simply that their machinery isn't working properly.

I think that calling a bad situation "screwed up" is also a reference to improperly adjusted machinery, not derived from the sexual meaning of "screw".

Rich Addison.