disposal sale; surplus goods sale
A sale event where excess, discontinued, or unwanted items are sold off, often at reduced prices. The term is not extremely common but is understood in commercial contexts.
They're having a disposal sale at the department store.
This is furniture I bought cheaply at a surplus sale.
Compound of 処分 (disposal) and 市 (market/sale). The exact historical derivation is uncertain, but it follows a common pattern for naming commercial events.