In finance, a dark pool is a private exchange for trading financial instruments such as securities. It differs from other exchanges in that its order is not public, only the exchange operators have access to it. Thus, it is not possible to see how much liquidity exists on either side of the market. The name comes from the fact that price discovery is not possible in dark pools. Since the trades are not revealed until sometime after their execution, the market is no longer transparent.
Read more: https://medium.com/@moonxfamily/what-is-deep-ocean-in-blockchain-space-e61f7c72e753