Not what something is worth in general. What it trades for the moment you actually try to sell it.
The spot price is the price of an asset for immediate delivery and payment, as opposed to a futures or forward price — a price agreed now for a transaction that settles later. The two rarely match: futures prices embed expectations, storage costs, and risk premiums the spot market doesn’t carry, and the gap between them (the “basis”) is itself a tradeable, studied quantity in commodity markets.
Repaying a debt “at spot price” rather than at a rate fixed when the loan was made means neither party is betting on where the asset’s price will move — the amount owed simply tracks the asset’s actual value on the day it’s due, a specific, deliberate way of avoiding the fixed-rate exposure that both interest and currency-denominated debt otherwise carry.
Source: Gorton, G.B., Hayashi, F. & Rouwenhorst, K.G., “The Fundamentals of Commodity Futures Returns,” NBER Working Paper 13249, 2007.