Khalsa which means 'Pure' is the name given by Guru Gobind Singh to all Sikhs who have been baptised or initiated by taking Amrit in a ceremony called Amrit Sanchar. The first time that this ceremony took place was on Baisakhi, which fell on 13 April 1699 at Anandpur Sahib in India. The Sikhs celebrated the 300th anniversary of the day in 1999 with thousands of religious gatherings all over the world.
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Noun 1. the group of initiated Sikhs to which devout orthodox Sikhs are ritually admitted at puberty; founded by the tenth and last Guru in 1699 (hypernym) religion, faith (classification) Sikhism