diff --git a/src/engine/runtime.js b/src/engine/runtime.js
index 7ab5aa2b1..9c7f3e9e4 100644
--- a/src/engine/runtime.js
+++ b/src/engine/runtime.js
@@ -602,7 +602,7 @@ class Runtime extends EventEmitter {
             category: categoryInfo.name,
             colour: categoryInfo.color1,
             colourSecondary: categoryInfo.color2,
-            colorTertiary: categoryInfo.color3,
+            colourTertiary: categoryInfo.color3,
             args0: []
         };