Not at all a dumb question, since you don't do auctions. A reserve is a minimum amount (usually hidden from bidders) which must be bid in order for the item to be sold. It's really a "hedge" by the seller so the item doesn't go for far below what the seller estimates its "worth" is. I dislike the practice and have never used it; I prefer to let the market set the final auction price.
Regards, Rob
