diff --git a/packages/core/lib/segments/attributes/subsegment.d.ts b/packages/core/lib/segments/attributes/subsegment.d.ts
index 5e012e4f..b827e0ea 100644
--- a/packages/core/lib/segments/attributes/subsegment.d.ts
+++ b/packages/core/lib/segments/attributes/subsegment.d.ts
@@ -62,7 +62,7 @@ declare class Subsegment {
 
   toJSON(): { [key: string]: any };
 
-  serialize(object?: Subsegment): string;
+  serialize(subsegment?: Subsegment): string;
 }
 
 export = Subsegment;