Anyone could win instantly by pointing out git. The hype is new, but not the concept.
"A blockchain is a growing list of records, called blocks, that are linked together using cryptography.[1][2][3][4] Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data (generally represented as a Merkle tree). [etc]"
Do you have a definition that git doesn't fit into (without getting too pedantic, e.g., git being a DAG of records rather than a list)?