Use of shared secret "other" than key creation I have read and (believe) I understand the basics of key exchange / creation over a public channel of communication from this diagram Diffie–Hellman key exchange.

Now, a fair bit of the online documentation states what has been produced by this process is a "shared secret" not a "shared secret key", nor any references to keys. The documentation does indicate what has been produced can be used as a (shared private?) key. But is the "shared secret" ever used for anything other than a key - I can't think what, but that's why I am asking the question. It was just the term "shared secret" without reference to "key" that prompts this question.

Edit:

This has been answered (but I can't find a way to indicate that on this post), so see comments below and : How to encrypt a symmetric key with a shared secret?
Shared secrets can also be used for authentication. He who knows the shared secret, is trusted.
For instance, this is used in IoT scenarios, where nodes communicate via DTLS and use the secret as a PSK instead of a certificate and a keypair.

Of course, this only makes sense if the shared secret has been preshared or calculated via some algorithm. The result of an online key agreement like DH cannot be used for that.