docs: add template ref var to glossary (#36743)

There is not an entry in the glossary for template
reference variable. To clarify for site visitors,
we are adding one here.

PR Close #36743

aio/content/guide/glossary.md

@@ -939,6 +939,19 @@ A TypeScript-like syntax that Angular evaluates within a [data binding](#data-bi
 
 Read about how to write template expressions in the [template expressions](guide/interpolation#template-expressions) section of the [Interpolation](guide/interpolation) guide.
 
+{@a template-reference-variable}
+
+## template reference variable
+
+A variable defined in a template that references an instance associated with an element, such as a directive instance, component instance, template as in `TemplateRef`, or DOM element.
+After declaring a template reference variable on an element in a template,
+you can access values from that variable elsewhere within the same template.
+The following example defines a template reference variable named `#phone`.
+
+<code-example path="template-reference-variables/src/app/app.component.html" region="ref-var" header="src/app/app.component.html"></code-example>
+
+For more information, see the [Template reference variable](guide/template-reference-variables) guide.
+
 {@a token}
 
 ## token

aio/content/guide/template-reference-variables.md

@@ -19,6 +19,13 @@ Here, a `<button>` further down the template refers to the `phone` variable.
 
 <code-example path="template-reference-variables/src/app/app.component.html" region="ref-phone" header="src/app/app.component.html"></code-example>
 
+Angular assigns each template reference variable a value based on where you declare the variable:
+
+* If you declare the variable on a component, the variable refers to the component instance.
+* If you declare the variable on a standard HTML tag, the variable refers to the element.
+* If you declare the variable on an `<ng-template>` element, the variable refers to a `TemplateRef` instance, which represents the template.
+* If the variable specifies a name on the right-hand side, such as `#var="ngModel"`, the variable refers to the directive or component on the element with a matching `exportAs` name.
+
 <h3 class="no-toc">How a reference variable gets its value</h3>
 
 In most cases, Angular sets the reference variable's value to the element on which it is declared.