diff --git a/guides/source/testing.md b/guides/source/testing.md
index 7d3da22597d3c6c881e0739b4ee42dddfb9fc20c..7ed102196fabf111f344f788e2cd00f00eec63c0 100644
--- a/guides/source/testing.md
+++ b/guides/source/testing.md
@@ -212,7 +212,7 @@ Next, let's look at our first assertion:
 assert true
 ```
 
-This line of code is called an _assertion_. An assertion is a line of code that evaluates an object (or expression) for expected results. For example, an assertion can check:
+An assertion is a line of code that evaluates an object (or expression) for expected results. For example, an assertion can check:
 
 * does this value = that value?
 * is this object nil?