The trade has a short vocabulary and it is worth using precisely, because these words carry price.
The terms
Deadstock (DS) — never worn, with the original box. Not "barely worn". Never.
VNDS — "very near deadstock". Tried on, or worn once or twice, with no meaningful wear. The honest use is narrow.
Used, with a description — everything else. This is where most pairs live and where precision pays.
Beaters — worn hard, sold as such. An honest category, not an insult.
What to describe, specifically
Creasing — where, and how deep.
Sole wear — even, or on one edge.
Yellowing — on the midsole, the outsole, or the upper, and under what light you are judging it.
Heel collapse.
Repairs or replacements — a re-glued sole, replaced laces, aftermarket insoles. All of these must be said.
Why precision pays
A bidder reading "good condition" prices the uncertainty. A bidder reading "light creasing on both toe boxes, soles even, no yellowing" prices the shoe. The arithmetic.
What the box state is worth saying
For a deadstock pair, say whether the box is intact, has a label, or is damaged. It is part of the item and leaving it vague invites a dispute.
Questions people ask
Is "VNDS" a real grade?
It is trade shorthand, not a graded standard. Describe what you mean by it.
Does a replaced insole matter?
To a collector, yes. Say it.
What if I do not know whether they were worn?
Say that. An unknown described as unknown is fine; an unknown described as deadstock is a dispute.
More: condition words across every category, describing condition.