Okay, I give up. I try to use new terms with some precision. Communication is better that way. But invariably, the marketers and the general press swoop in, half-understanding the new concept, and start throwing the new lingo around. Soon, it’s little better than jargon.
A block chain is one way of technically implementing a distributed ledger. Blockchain technology has its pros and cons, and there’s a lot of active work going on to find alternatives for distributed ledgers that avoid blockchain’s disadvantages. So there’s a good chance that the next “blockchain” project you find yourself working on or implementing won’t actually use a block chain. It might use a Distributed Acyclic Graph (DAG), or something else.
But chances are, you’ll still call it a blockchain project. So go ahead and call it that. Words change in meaning, terminology evolves rapidly. As long as we all know what we’re talking about, that’s all that matters.