message: docs(elements): add angular element term to glossary
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diff: @@ -28,6 +28,11 @@ By compiling your application using the `ngc` command-line tool, you can bootstr
  Compare [just-in-time (JIT) compilation](guide/glossary#jit).
  +## Angular element
  +
  +An Angular [component](guide/glossary#component) that has been packaged as a [custom element](guide/glossary#custom-element).
  +
  +Learn more in the [_Angular Elements_](guide/elements) guide.
  ## Annotation
  