diff --git a/types/node-gettext/index.d.ts b/types/node-gettext/index.d.ts
index 5aeb0bf262..6388c77af3 100644
--- a/types/node-gettext/index.d.ts
+++ b/types/node-gettext/index.d.ts
@@ -5,6 +5,9 @@
 // TypeScript Version: 2.2
 export = GetText;
 declare class GetText {
+    static getLanguageCode(locale: string): string;
+    readonly locale: string;
+    readonly domain: string;
     constructor(options?: { debug?: boolean; sourceLocale?: string });
     addTranslations(locale: string, domain: string, translations: object): void;
     dgettext(domain: string, msgid: string): string;
@@ -16,12 +19,11 @@ declare class GetText {
     gettext(msgid: string): string;
     ngettext(msgid: string, msgidPlural: string, count: number): string;
     npgettext(msgctxt: string, msgid: string, msgidPlural: string, count: number): string;
-    off(eventName: 'error', callback: (error: any) => void): void;
-    on(eventName: 'error', callback: (error: any) => void): void;
+    off(eventName: 'error', callback: (error: Error) => void): void;
+    on(eventName: 'error', callback: (error: Error) => void): void;
     pgettext(msgctxt: string, msgid: string): string;
     setLocale(locale: string): void;
     setTextDomain(domain: string): void;
-    static getLanguageCode(locale: string): string;
     textdomain(domain: string): void;
     warn(message: string): void;
 }