"As New", "NOS", etc

I've seen quite a few ads using these terms, often quite loosely.

Just what the heck does "As New" mean? Something someone used and put back in the box and expects full retail price?

And "NOS"; shouldn't that mean an old, never sold, unopened item, and not something someone used a few times and put back in the box?

I can't find anything on the Audiogon listing guidelines about this.
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You are right. All these "NOS" offers are wrong.

NOS IS New in the Box.
Normally you can get those only from dealers who bought thousands for a few pence/piece (most boxes had 1000 in it) and now they can realize a better rating than Apple shares :-)
As new ,NOS all Jive!!
I saw an ad today for a piece that had been described as opened two weeks ago and used for 30 minutes being sold "as new". If this is accurate, I would agree that "as new" is a reasonable description. What was also interesting is that the seller had a discount of 7% from MSRP. I would rather just by new I think.

I just did by some NOS tubes from a company that I trust as being truly NOS. I am sure that many are not really NOS. I really wonder who buys these from e-bay?