diff --git a/DDG4/include/DDG4/Geant4FastSimShowerModel.h b/DDG4/include/DDG4/Geant4FastSimShowerModel.h
index cd8ed73ae098ac60d811f3bea1ecd4c168fb3d2f..b158999b6fd9f09f959985db8d00b1212e5bb1d9 100644
--- a/DDG4/include/DDG4/Geant4FastSimShowerModel.h
+++ b/DDG4/include/DDG4/Geant4FastSimShowerModel.h
@@ -60,7 +60,7 @@ namespace dd4hep  {
       std::vector<std::string> m_applicablePartNames  { };
       /// Property: Parametrisation control: Enable/disable fast simulation
       bool           m_enable         { false };
-      /// Property: Defines step lenght
+      /// Property: Defines step length
       double         m_stepX0         { 0.1 };
       /// Property: Set minimum kinetic energy to trigger parametrisation
       ParticleConfig m_eMin           { };
diff --git a/DDG4/python/DDG4.py b/DDG4/python/DDG4.py
index a643d8dd6629a0d4df6c84e23661e1a773c30d89..f6ff67f58ef389db35030cf042be07fe9179686c 100644
--- a/DDG4/python/DDG4.py
+++ b/DDG4/python/DDG4.py
@@ -474,7 +474,7 @@ class Geant4:
                               sensitives=None, sensitives_args=None,
                               allow_threads=False):
     """
-    Configure Geant4 user initialization for optionasl multi-threading mode
+    Configure Geant4 user initialization for optional multi-threading mode
 
     \author  M.Frank
     """