diff --git a/docs/explanations/about_esm.md b/docs/explanations/about_esm.md
index efed6b7d0a..7cc86ea46d 100644
--- a/docs/explanations/about_esm.md
+++ b/docs/explanations/about_esm.md
@@ -76,7 +76,7 @@ installed by apt (in `install` or `upgrade`) or by unattended-upgrades will
 always be the highest `esm` version available for a given package, even if a
 higher version is present on a non-esm source.
 
-This behavior guarantees that if you have `esm-infra` or `esm-apps` enabled,
+This behaviour guarantees that if you have `esm-infra` or `esm-apps` enabled,
 your system will always have the `esm` patches installed for any package
 available in the ESM repositories.