unredeemed pawned item; forfeited article
Refers to an item left at a pawnshop beyond the redemption period, which then becomes the property of the pawnbroker and may be sold.
There are shops where you can buy unredeemed pawned items cheaply.
This watch is a forfeited item; the original owner didn't come to redeem it by the deadline.
質屋 is the pawnshop itself, not the item.
Compound of 質 (しち, 'pawn') + 流れ (ながれ, 'flowing away, forfeiture') + 品 (ひん, 'item'). The term literally means 'pawn-flow-item', referring to an item that has flowed out of the pawn contract.