Singh (meaning Lionसिंह) is a middle name or surname used in South Asia, mainly in India. The Punjabi (warriors, administrators and kings) are examples of certain roles held by those in Punjab who had adopted the last name. Singh as a middle name or last name was first used in Rajasthan, Uttar Pradesh, Haryana, Bihar, Madhya Pradesh rather than popular belief of Sikhs or in Punjab. Punjab adopted later than other North Indians.
It is derived from the Sanskrit word सिंह siṃha/sinha meaning lion. It is used as a surname or middle name by Hindu communities including Jats, Gurjars, Rajputs, Rajanya Kayasthas, Kurmis, Yadavs, Manipuris, Bengali Hindus and Ahirs, as well as by Sikhs, for whom it is mandatory. The surname is generally used by males.
By the sixteenth century, "Singh/Sinha" had become a popular surname among Rajput warriors and Royal Kayastha administrators/lords.
It was adopted into Sikhism in 1699 as per the instructions of Guru Gobind Singh; the use of Singh as a last name is mandatory for all baptized male Sikhs since 1699, regardless of their geographical or cultural binding.
Some Brahmins, such as Bhumihar Brahmins, Maithil Brahmins also use this surname in Bihar. The anthropologist Kumar Suresh Singh said in People of India (Bihar and Jharkhand), published by the Anthropological Survey of India (ASI) that the surname "Singh/Sinha", used to denote connection with power and authority, was now used in Bihar by Brahmin and Kayastha zamindars, like the surname "Khan" is used by Muslims.
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