diff --git a/scss/_variables.scss b/scss/_variables.scss
index e2bacef4af57..bf9916388879 100644
--- a/scss/_variables.scss
+++ b/scss/_variables.scss
@@ -239,6 +239,7 @@ $font-size-base: 1rem !default; // Assumes the browser default, typically `16px`
 $font-size-lg:   1.25rem !default;
 $font-size-sm:   .875rem !default;
 
+$font-weight-light: light !default;
 $font-weight-normal: normal !default;
 $font-weight-bold: bold !default;