A child block of an ancestor that is not itself an ancestor. When a miner finds a valid block, another miner may have published a competing block which is added to the tip of the blockchain. Unlike with Bitcoin, orphaned blocks in Ethereum can be included by newer blocks as ommers and receive a partial block reward. The term “ommer” is the preferred gender-neutral term for the sibling of a parent block, but this is also sometimes referred to as an “uncle.”

Search across the site