diff --git a/src/core/Geometry.d.ts b/src/core/Geometry.d.ts
index b369c3e65cea15c6406c4631036ece5a63ced3b5..52b8bd7b91499f5ee595a8e3406889128081b47d 100644
--- a/src/core/Geometry.d.ts
+++ b/src/core/Geometry.d.ts
@@ -49,6 +49,8 @@ export class Geometry extends EventDispatcher {
 	id: number;
 
 	uuid: string;
+	
+	isGeometry: boolean;
 
 	/**
 	 * Name for this geometry. Default is an empty string.