Spreadlock

Like dreadlocks, only for people who are going bald...big blank patches between each of the dreads.

In the financial world, the "spread" in question here is the difference between an interest rate swap and the rate offered on underlying government bonds. This spread can move over time, so the holder of a swap can lose out if the spread changes in an unfavorable way.

As its name suggests, the spreadlock allows the holder of the swap to lock the spread in place. It's a form of derivative contract that hedges against possible changes in the relationship between the swap rate and the government bond rate.