diff --git a/lang/en_utf8/lesson.php b/lang/en_utf8/lesson.php
index fae21fb011e..0337544debb 100644
--- a/lang/en_utf8/lesson.php
+++ b/lang/en_utf8/lesson.php
@@ -255,7 +255,7 @@ $string['showanunseenpage'] = 'Show an Unseen Page';
 $string['singleanswer'] = 'Single Answer';
 $string['skip'] = 'Skip navigation';
 $string['slideshow'] = 'Slide Show';
-$string['slideshowbgcolor'] = 'Slide show background color';
+$string['slideshowbgcolor'] = 'Slide show background colour';
 $string['slideshowheight'] = 'Slide show height';
 $string['slideshowwidth'] = 'Slide show width';
 $string['startlesson'] = 'Start lesson';