a holiday observed in some countries of the Commonwealth of Nations, originally on May 24, the anniversary of Queen Victoria's birth, but now on varying dates.
Origin of Commonwealth Day
First recorded in 1955–60
Formerly Empire Day.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for commonwealth day
the anniversary of Queen Victoria's birth, May 24, celebrated (now on the second Monday in March) as a holiday in many parts of the CommonwealthFormer name: Empire Day
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012