The abbreviation commonly used for International Women's Day is IWD.
The initials come directly from the event's English name: International Women's Day. IWD is widely used by the United Nations, governments, charities, workplaces, news organizations and campaign groups, especially in headlines, event names and social-media hashtags such as #IWD.
International Women's Day is observed annually on 8 March. Its modern meaning includes celebrating women's social, economic, cultural and political achievements while drawing attention to continuing inequality, discrimination, violence and reproductive-rights issues. The observance grew out of early twentieth-century labor and socialist movements rather than beginning as a purely commercial holiday.
Do not confuse IWD with International Men's Day, often abbreviated IMD, or with International Women's Year, abbreviated IWY. Another common mix-up is assuming that IWD has always had one fixed date: early Women's Day observances used different dates before 8 March became standard internationally.