diff --git a/src/lib/dhcpsrv/memfile_lease_mgr.h b/src/lib/dhcpsrv/memfile_lease_mgr.h
index 5975e5ff53..3273ee4839 100644
--- a/src/lib/dhcpsrv/memfile_lease_mgr.h
+++ b/src/lib/dhcpsrv/memfile_lease_mgr.h
@@ -506,7 +506,7 @@ public:
 
 private:
 
-    /// @name Internal methods called holding the mutex in multi threading
+    /// @name Internal methods called while holding the mutex in multi threading
     /// mode.
     ///@{
 
diff --git a/src/lib/dhcpsrv/timer_mgr.cc b/src/lib/dhcpsrv/timer_mgr.cc
index cc5a879b89..f71b768ba0 100644
--- a/src/lib/dhcpsrv/timer_mgr.cc
+++ b/src/lib/dhcpsrv/timer_mgr.cc
@@ -149,7 +149,7 @@ public:
 
 private:
 
-    /// @name Internal methods called holding the mutex in multi threading
+    /// @name Internal methods called while holding the mutex in multi threading
     /// mode.
 
     /// @brief Registers new timer in the @c TimerMgr.