diff --git a/addons/web/static/src/core/effect_hook.js b/addons/web/static/src/core/effect_hook.js
index 91ae4e8df69..7e2b298e97d 100644
--- a/addons/web/static/src/core/effect_hook.js
+++ b/addons/web/static/src/core/effect_hook.js
@@ -4,8 +4,8 @@ const { onMounted, onWillPatch, onPatched, onWillUnmount } = owl.hooks;
 const NO_OP = () => {};
 /**
  * @callback Effect
- * @param {...any} dependencies the dependecies computed by computeDependencies
- * @returns {()=>void)?} a cleanup function that reverses the side
+ * @param {...any} dependencies the dependencies computed by computeDependencies
+ * @returns {void|(()=>void)} a cleanup function that reverses the side
  *      effects of the effect callback.
  */