diff --git a/docs/ce1/ece105.md b/docs/ce1/ece105.md
index ce0174c..c974903 100644
--- a/docs/ce1/ece105.md
+++ b/docs/ce1/ece105.md
@@ -157,8 +157,8 @@ $$\vec L =\vec\tau t$$
 ## Rolling motion
 
 !!! definition
-    - **Slipping** is spinning without sliding.
-    - **Skidding** is sliding without spinning.
+    - **Slipping** is sliding faster than spinning.
+    - **Skidding** is spinning faster than sliding.
 
 Pure rolling motion is **only true if** the tangential velocity of the centre of mass is equal to its rotational velocity.