diff --git a/docs/content/sequenceDiagram.md b/docs/content/sequenceDiagram.md
index 8261456b3..a5c3141c6 100755
--- a/docs/content/sequenceDiagram.md
+++ b/docs/content/sequenceDiagram.md
@@ -190,7 +190,7 @@ else
 end
 ```
 
-or if there is sequence that is optionat (if without else).
+or if there is sequence that is optional (if without else).
 
 ```
 opt Describing text