What is the meaning of Ik Onkar (Sikh religious symbol)?

Ik Onkar, also spelled Ek Onkar is a phrase in Sikhism that denotes the one supreme reality. It is a central tenet of Sikh religious philosophy.

Ik Onkar are the first words of the Mul Mantar and also the opening words of the Sikh holy scripture Guru Granth Sahib.

Ik is interpreted as "one and only one, who cannot be compared or contrasted with any other",the "unmanifest, God in power, the holy word, the primal manifestation of Godhead by which and in which all live, move and have their being and by which all find a way back to Absolute God, the Supreme Reality."

Ik Onkar has a distinct spelling in the Gurmukhi script and the phrase is found in many Sikh religious scriptures and inscribed in places of worship such as gurdwaras.