In financial terminology, backwardation means a downward sloping forward curve (as in an inverted yield curve). A backwardation starts when the difference between the forward price and the spot price is less than the cost of carry, or when there can be no delivery arbitrage because the asset is not currently available for purchase.

The opposite market condition to backwardation is known as contango, in which the expected spot price at maturity is lower than the forward price. Futures contract price includes compensation for the risk transferred from the asset holder. This makes actual price on expiry to be lower than futures contract price. Backwardation very seldom arises in money commodities like gold or silver. In the early 1980s, there was a one-day backwardation in silver while some metal was physically moved from COMEX to CBOT warehouses.[Gold has historically been positive with exception for momentary backwardations (hours) since gold futures started trading on the Winnipeg Commodity Exchange in 1972.

The term is sometimes applied to forward prices other than those of futures contracts, when analogous price patterns arise. For example, if it costs more to lease silver for 30 days than for 60 days, it might be said that the silver lease rates are "in backwardation".
额 是问这个么。。。

其实很简单，在期货和远期市场中，有个概念就是远期的价格比即期价格高，即称为congtango升水，反之称为backwardation贴水