Everybody has taken to calling blockchain a "distributed ledger technology".
At least from 2015 and the famous article in "The Economist" called "The Trust Machine" in which it was said
The blockchain is an even more potent technology. In essence it is a shared, trusted, public ledger that everyone can inspect, but which no single user controls.
(on a side note, remember when bitcoin "had been stable at around $250 for most of the year"? That's another quote from the same article)
However now, the very well regarded International Standards Organisation (ISO) has taken to establishing a terminology for blockchain systems in its Technical Committee 307 (TC 307), dedicated to "Blockchain and distributed ledger technologies" .
When reading its recently circulated Terminology Working Draft N 318 from July 25th 2018, I was suddenly a bit embarrassed upon falling upon this:
distributed ledger (3.19)
That is because I am no accountant but I know enough accounting to know that, despite what the newspapers and the general public has taken to believe, blockchains are NOT ledgers but "journals".
An accounting journal is different, very different from a ledger, at least to an accountant.
Of course for me or any normal person, I can sleep very well without knowing the difference between a "ledger" and a "journal".
As an IT person I am perfectly happy to go with the stream and talk about "distributed ledgers". Why would I want to appear as a "know it all" by insisting on "correct accounting terminology" when I'm not even an accountant myself!
But the problem here is that we are in a very formal setting: that of ISO and IEC which happen to have official definitions for these terms, definitions you can find here.
A blockchain does not have "debits, credits, and all other money transactions under each individual account or heading", the data is not organized. Thus it is not a ledger.
A blockchain does have a set of recorded, time-tagged event transactions, variable data, and/or comments, that may be logically ordered during retrieval.
So, while for the layman that I am, calling blockchain "a distributed ledger" is perfectly dandy, I do not see how can ISO justify catching its feet into its own carpet …
For ISO, in order for its own body of knowledge (its ontology) to remain consistent, a blockchain has to be "a distributed journal", not a distributed ledger, regardless of what the non-accounting oriented journalists and IT people want to call it …