Orphan (Also Called Orphan Block)

Also logically known as “Orphan Block” Orphans are considered to be stale blocks that are not admitted into the blockchain network. The non-acceptance of these blocks is owed to the lag in time in accepting that block into the blockchain. 

While considered valid and had therefore been duly verified, an Orphan Block is simply a block one that had been rejected by the chain. These may be brought into existence upon the production of blocks by two miners at the same time. It may also be owed to an attacker who is attempting to reverse certain transactions. An Orphan Block is also sometimes known as a “detached block.”