diff --git a/include/core/Quaternion.hpp b/include/core/Quaternion.hpp
index d8a806a..6f8f20d 100644
--- a/include/core/Quaternion.hpp
+++ b/include/core/Quaternion.hpp
@@ -28,8 +28,8 @@
 /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
 /*************************************************************************/
 
-#ifndef QUAT_H
-#define QUAT_H
+#ifndef QUATERNION_H
+#define QUATERNION_H
 
 #include <cmath>