diff --git a/src/include/units/unit.h b/src/include/units/unit.h
index 8010dba1..14aa5649 100644
--- a/src/include/units/unit.h
+++ b/src/include/units/unit.h
@@ -79,13 +79,6 @@ struct unit : downcast_child<Child, scaled_unit<ratio(1), Child>> {
   using prefix_family = no_prefix;
 };
 
-/**
- * @brief Unknown unit
- * 
- * Used as a coherent unit of an unknown dimension.
- */
-struct unknown_coherent_unit : unit<unknown_coherent_unit> {};
-
 /**
  * @brief A named unit
  *
@@ -259,4 +252,11 @@ struct prefixed_alias_unit : U {
   using prefix_family = no_prefix;
 };
 
+/**
+ * @brief Unknown unit
+ * 
+ * Used as a coherent unit of an unknown dimension.
+ */
+struct unknown_coherent_unit : unit<unknown_coherent_unit> {};
+
 }  // namespace units