This thing, however, exists only for the purpose of solving decentralized trust problem and cannot be secure without a popular public cryptocurrency. Hence private blockchain is a fallacy. If trust relies on authority it's just a weird database, not a "private" blockchain.
It's similar to how people were annoyed with the commons clause added to an open source license being associated with the same old unrestricted license, that in fact became a completely different license.
> chain of hash-based proof-of-work
and
> chain of blocks
in this paper. His later communication does call this "block chain".
So you are right that he/them/she does not use the term "blockchain" in the paper. Nor "block chain" but the term can be extracted from there clearly.
Context from referred Nakamoto pdf: In this paper, we propose a solution to the double-spending problem using a peer-to-peer distributed timestamp server to generate computational proof of the chronological order of transactions
So this is not definition of blockchain by Nakamoto (There is no term blockchain at all in this pdf)
Definition from wikipedia (I agree with): A blockchain is a growing list of records, called blocks, which are linked using cryptography. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data (generally represented as a merkle tree root hash)
From this definition git is also kind of blockchain.
So its hard to follow article with such vague definition from start.