Add higher-order component (HOC) definition

docs/glossary.md

@@ -871,4 +871,18 @@ variation
     Extending this example, a developer can add a boolean field to the block that toggles the display of the link.
     Thus an editor can select between `title + link` or just `title`.
 
+HOC
+Higher-Order Component
+    A higher-order component (HOC) is an advanced technique in React for reusing component logic.
+    HOCs are not part of the React API, per se.
+    They are a pattern that emerges from React's compositional nature.
+    Concretely, a higher-order component is a function that takes a component and returns a new component.
+    
+    ```{important}
+    Higher-order components are not commonly used in modern React code.
+    ```
+    ```{seealso}
+    https://legacy.reactjs.org/docs/higher-order-components.html
+    ```
+
 ```