While, Sikhism (); Punjabi: ਸਿੱਖੀ or Sikhi ("Sikkhī", ], from ਸਿੱਖ, "Sikh", 'disciple', 'seeker', or 'learner'), is a monotheistic religion that originated in the Punjab region of the Indian subcontinent around the end of the 15th century CE. One of the youngest of the major religions and the world's fifth-largest organized religion, it comprises about 25 million Sikhs as of the early-21st century. However, according to rough estimates, there are around 120–150 million (12–15 crore) Nanak Naam Lewas people across the world who also believe in 10 Sikh gurus and the "Guru Granth Sahib".