A hard spoon is a meta-protocol that exists on top of a blockchain.
A spoon is a type of blockchain fork where the new cryptocurrency inherits the account balances of an existing cryptocurrency. It allows a new project to add its own features to the previous software, whilst still allowing the users of the existing protocol to participate in it. Projects spoon in order to attract users and developers of an established platform. They are more amicable than contentious in nature. However, they are very not common in the blockchain industry since their implementation isn’t exactly convenient.
A spoon differs from the more common hard fork by its nature and intention. Most hard forks are contentious, while spoons are collaboration-focused. Hard forks also use the same token as the existing chain, whilst spoons merely copy balances and use another custom token for their purposes. Furthermore, hard forks are designed to steal market share and dominance of an existing platform, while spoons complement the technical prowess of the projects they copy balances from.
Thanks to its large user base and developer community, Ethereum is the most used protocol for spooning. Typical examples include Athereum and Cosmos, both of which took snapshots of the Ethereum blockchain to note and port account balances on their new networks. Unsurprisingly, these networks are compatible with the Ethereum mainnet in various ways and also introduce their own improvements/functionalities to it. But despite copying balances, they have their own tokens and don’t use ETH.