diff --git a/spec/quantities.yaml b/spec/quantities.yaml
index 3babc060..6764d0b6 100644
--- a/spec/quantities.yaml
+++ b/spec/quantities.yaml
@@ -67,7 +67,8 @@ distance-per-volume:
 force:
   definition: Vector quantity describing interaction between bodies or particles (ISO 80000-4:2019)
 torque:
-  definition: quantity described by the scalar product M*eQ where M is moment of force and eQ is
+  definition: Quantity described by the scalar product M*eQ where M is moment of force and
+              eQ is unit vector of direction with respect to which the torque is considered (ISO 80000-4:2019)
 rotational-speed:
   definition: TBD
 frequency: