Economy Brexit basics: What is Brexit and why does it matter? Updated : December 18, 2018 07:55 PM IST The date is set in law - the 2018 Withdrawal Act - but the divorce has been plunged into chaos. A blending of "Britain" and "exit," it is the description of the United Kingdom's decision to leave the European Union. Subscribe to Moneycontrol PRO at just Rs.33/- per month for the first year. Use code SUPERPRO. Limited period offer. Available on Web and Android.