diff --git a/src/ch04/s05-fail.md b/src/ch04/s05-fail.md
index 0a46398..7a726cd 100644
--- a/src/ch04/s05-fail.md
+++ b/src/ch04/s05-fail.md
@@ -1,10 +1,10 @@
 # Fail Semantics
 
-## Lack of proper support for injecting errors into classes that are already `Fail`
-* Classes have only one implementation of `Fail` per error type.
+## Lack of proper support for injecting errors into instances that are already `Fail`
+* Instances have only one implementation of `Fail` per error type.
 * Proposed solutions:
-  * Have `Fail` as a separate trait with the error and the class as associated types.
-  * `OverloadClass` to mix-in additional `Fail`.
+  * Have `Fail` as a separate trait with the error and the instances as associated types.
+  * `OverloadInstance` to mix-in additional `Fail`.
 
 ## ~~Lack of support for strict ordering of errors~~
 * ~~Current (possible) implementations of having one error or another either allow short-circuiting on only one of them, or give them both the same priority. **Right now this model is considered the main one**, i.e. this restriction may get stabilised and standardised at some point.~~