A contentious fork is a hard fork stemming from a disagreement in how the blockchain should process blocks. The most famous example of a contentious fork is when Bitcoin Cash forked the chain over a disagreement of the block size limit. Another example is when Ethereum hard forked in response to the DAO hack which lead to the creation of Ethereum Classic (ETC). Contentious forks lead to an entirely separate blockchain with a new coin.

Word missing from the glossary or definition needs improvement? Let us know!