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Satnam
Satnam ( Gurmukhi:ਸਤਿ ਨਾਮੁ ) is the main word that appears in the Sikh sacred scripture called the Guru Granth Sahib. It is part of the Gurbani shabad called Mool Mantra which is repeated daily by all Sikhs. This word succeeds the word " Ek-onkar" which means "There is only one constant" or commonly "There is one God". The words sat means "true/everlasting" and nam means "name". In this instance, this would mean, "whose name is truth".
The word nam in Sikhism has two meanings. "It meant both an application and a symbol of the All-pervading Supreme Reality that sustained the universe. Guru Nanak in his teachings emphasized the need of repeating Sat-Nam to realize the All-pervading Supreme Reality."